database/postgres
database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-04-25 21:42:33 +03:00
Code
postgres/src/backend/parser/analyze.c
Tom Lane 1f5ca045a4 Disallow aggregate functions in UPDATE commands (unless within a sub-SELECT). 
This is disallowed by the SQL spec because it doesn't have any very sensible
interpretation.  Historically Postgres has allowed it but behaved strangely.
As of PG 8.1 a server crash is possible if the MIN/MAX index optimization gets
applied; rather than try to "fix" that, it seems best to just enforce the
spec restriction.  Per report from Josh Drake and Alvaro Herrera.
2006-06-21 18:30:11 +00:00

3254 lines
91 KiB
C
Raw Blame History

/*-------------------------------------------------------------------------
*
* analyze.c
* transform the parse tree into a query tree
*
* Portions Copyright (c) 1996-2006, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/backend/parser/analyze.c,v 1.335 2006/06/21 18:30:11 tgl Exp $
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "access/heapam.h"
#include "catalog/heap.h"
#include "catalog/index.h"
#include "catalog/namespace.h"
#include "catalog/pg_index.h"
#include "catalog/pg_type.h"
#include "commands/defrem.h"
#include "commands/prepare.h"
#include "miscadmin.h"
#include "nodes/makefuncs.h"
#include "optimizer/clauses.h"
#include "optimizer/var.h"
#include "parser/analyze.h"
#include "parser/gramparse.h"
#include "parser/parsetree.h"
#include "parser/parse_agg.h"
#include "parser/parse_clause.h"
#include "parser/parse_coerce.h"
#include "parser/parse_expr.h"
#include "parser/parse_oper.h"
#include "parser/parse_relation.h"
#include "parser/parse_target.h"
#include "parser/parse_type.h"
#include "parser/parse_expr.h"
#include "rewrite/rewriteManip.h"
#include "utils/acl.h"
#include "utils/builtins.h"
#include "utils/fmgroids.h"
#include "utils/guc.h"
#include "utils/lsyscache.h"
#include "utils/relcache.h"
#include "utils/syscache.h"
/* State shared by transformCreateSchemaStmt and its subroutines */
typedef struct
{
const char *stmtType; /* "CREATE SCHEMA" or "ALTER SCHEMA" */
char *schemaname; /* name of schema */
char *authid; /* owner of schema */
List *sequences; /* CREATE SEQUENCE items */
List *tables; /* CREATE TABLE items */
List *views; /* CREATE VIEW items */
List *indexes; /* CREATE INDEX items */
List *triggers; /* CREATE TRIGGER items */
List *grants; /* GRANT items */
List *fwconstraints; /* Forward referencing FOREIGN KEY constraints */
List *alters; /* Generated ALTER items (from the above) */
List *ixconstraints; /* index-creating constraints */
List *blist; /* "before list" of things to do before
* creating the schema */
List *alist; /* "after list" of things to do after creating
* the schema */
} CreateSchemaStmtContext;
/* State shared by transformCreateStmt and its subroutines */
typedef struct
{
const char *stmtType; /* "CREATE TABLE" or "ALTER TABLE" */
RangeVar *relation; /* relation to create */
List *inhRelations; /* relations to inherit from */
bool hasoids; /* does relation have an OID column? */
bool isalter; /* true if altering existing table */
List *columns; /* ColumnDef items */
List *ckconstraints; /* CHECK constraints */
List *fkconstraints; /* FOREIGN KEY constraints */
List *ixconstraints; /* index-creating constraints */
List *blist; /* "before list" of things to do before
* creating the table */
List *alist; /* "after list" of things to do after creating
* the table */
IndexStmt *pkey; /* PRIMARY KEY index, if any */
} CreateStmtContext;
typedef struct
{
Oid *paramTypes;
int numParams;
} check_parameter_resolution_context;
static List *do_parse_analyze(Node *parseTree, ParseState *pstate);
static Query *transformStmt(ParseState *pstate, Node *stmt,
List **extras_before, List **extras_after);
static Query *transformViewStmt(ParseState *pstate, ViewStmt *stmt,
List **extras_before, List **extras_after);
static Query *transformDeleteStmt(ParseState *pstate, DeleteStmt *stmt);
static Query *transformInsertStmt(ParseState *pstate, InsertStmt *stmt,
List **extras_before, List **extras_after);
static Query *transformIndexStmt(ParseState *pstate, IndexStmt *stmt);
static Query *transformRuleStmt(ParseState *query, RuleStmt *stmt,
List **extras_before, List **extras_after);
static Query *transformSelectStmt(ParseState *pstate, SelectStmt *stmt);
static Query *transformSetOperationStmt(ParseState *pstate, SelectStmt *stmt);
static Node *transformSetOperationTree(ParseState *pstate, SelectStmt *stmt);
static Query *transformUpdateStmt(ParseState *pstate, UpdateStmt *stmt);
static Query *transformDeclareCursorStmt(ParseState *pstate,
DeclareCursorStmt *stmt);
static Query *transformPrepareStmt(ParseState *pstate, PrepareStmt *stmt);
static Query *transformExecuteStmt(ParseState *pstate, ExecuteStmt *stmt);
static Query *transformCreateStmt(ParseState *pstate, CreateStmt *stmt,
List **extras_before, List **extras_after);
static Query *transformAlterTableStmt(ParseState *pstate, AlterTableStmt *stmt,
List **extras_before, List **extras_after);
static void transformColumnDefinition(ParseState *pstate,
CreateStmtContext *cxt,
ColumnDef *column);
static void transformTableConstraint(ParseState *pstate,
CreateStmtContext *cxt,
Constraint *constraint);
static void transformInhRelation(ParseState *pstate, CreateStmtContext *cxt,
InhRelation *inhrelation);
static void transformIndexConstraints(ParseState *pstate,
CreateStmtContext *cxt);
static void transformFKConstraints(ParseState *pstate,
CreateStmtContext *cxt,
bool skipValidation,
bool isAddConstraint);
static void applyColumnNames(List *dst, List *src);
static List *getSetColTypes(ParseState *pstate, Node *node);
static void transformLockingClause(Query *qry, LockingClause *lc);
static void transformConstraintAttrs(List *constraintList);
static void transformColumnType(ParseState *pstate, ColumnDef *column);
static void release_pstate_resources(ParseState *pstate);
static FromExpr *makeFromExpr(List *fromlist, Node *quals);
static bool check_parameter_resolution_walker(Node *node,
check_parameter_resolution_context *context);
/*
* parse_analyze
* Analyze a raw parse tree and transform it to Query form.
*
* If available, pass the source text from which the raw parse tree was
* generated; it's OK to pass NULL if this is not available.
*
* Optionally, information about $n parameter types can be supplied.
* References to $n indexes not defined by paramTypes[] are disallowed.
*
* The result is a List of Query nodes (we need a list since some commands
* produce multiple Queries). Optimizable statements require considerable
* transformation, while many utility-type statements are simply hung off
* a dummy CMD_UTILITY Query node.
*/
List *
parse_analyze(Node *parseTree, const char *sourceText,
Oid *paramTypes, int numParams)
{
ParseState *pstate = make_parsestate(NULL);
List *result;
pstate->p_sourcetext = sourceText;
pstate->p_paramtypes = paramTypes;
pstate->p_numparams = numParams;
pstate->p_variableparams = false;
result = do_parse_analyze(parseTree, pstate);
pfree(pstate);
return result;
}
/*
* parse_analyze_varparams
*
* This variant is used when it's okay to deduce information about $n
* symbol datatypes from context. The passed-in paramTypes[] array can
* be modified or enlarged (via repalloc).
*/
List *
parse_analyze_varparams(Node *parseTree, const char *sourceText,
Oid **paramTypes, int *numParams)
{
ParseState *pstate = make_parsestate(NULL);
List *result;
pstate->p_sourcetext = sourceText;
pstate->p_paramtypes = *paramTypes;
pstate->p_numparams = *numParams;
pstate->p_variableparams = true;
result = do_parse_analyze(parseTree, pstate);
*paramTypes = pstate->p_paramtypes;
*numParams = pstate->p_numparams;
pfree(pstate);
/* make sure all is well with parameter types */
if (*numParams > 0)
{
check_parameter_resolution_context context;
context.paramTypes = *paramTypes;
context.numParams = *numParams;
check_parameter_resolution_walker((Node *) result, &context);
}
return result;
}
/*
* parse_sub_analyze
* Entry point for recursively analyzing a sub-statement.
*/
List *
parse_sub_analyze(Node *parseTree, ParseState *parentParseState)
{
ParseState *pstate = make_parsestate(parentParseState);
List *result;
result = do_parse_analyze(parseTree, pstate);
pfree(pstate);
return result;
}
/*
* do_parse_analyze
* Workhorse code shared by the above variants of parse_analyze.
*/
static List *
do_parse_analyze(Node *parseTree, ParseState *pstate)
{
List *result = NIL;
/* Lists to return extra commands from transformation */
List *extras_before = NIL;
List *extras_after = NIL;
Query *query;
ListCell *l;
query = transformStmt(pstate, parseTree, &extras_before, &extras_after);
/* don't need to access result relation any more */
release_pstate_resources(pstate);
foreach(l, extras_before)
result = list_concat(result, parse_sub_analyze(lfirst(l), pstate));
result = lappend(result, query);
foreach(l, extras_after)
result = list_concat(result, parse_sub_analyze(lfirst(l), pstate));
/*
* Make sure that only the original query is marked original. We have to
* do this explicitly since recursive calls of do_parse_analyze will have
* marked some of the added-on queries as "original". Also mark only the
* original query as allowed to set the command-result tag.
*/
foreach(l, result)
{
Query *q = lfirst(l);
if (q == query)
{
q->querySource = QSRC_ORIGINAL;
q->canSetTag = true;
}
else
{
q->querySource = QSRC_PARSER;
q->canSetTag = false;
}
}
return result;
}
static void
release_pstate_resources(ParseState *pstate)
{
if (pstate->p_target_relation != NULL)
heap_close(pstate->p_target_relation, NoLock);
pstate->p_target_relation = NULL;
pstate->p_target_rangetblentry = NULL;
}
/*
* transformStmt -
* transform a Parse tree into a Query tree.
*/
static Query *
transformStmt(ParseState *pstate, Node *parseTree,
List **extras_before, List **extras_after)
{
Query *result = NULL;
switch (nodeTag(parseTree))
{
/*
* Non-optimizable statements
*/
case T_CreateStmt:
result = transformCreateStmt(pstate, (CreateStmt *) parseTree,
extras_before, extras_after);
break;
case T_IndexStmt:
result = transformIndexStmt(pstate, (IndexStmt *) parseTree);
break;
case T_RuleStmt:
result = transformRuleStmt(pstate, (RuleStmt *) parseTree,
extras_before, extras_after);
break;
case T_ViewStmt:
result = transformViewStmt(pstate, (ViewStmt *) parseTree,
extras_before, extras_after);
break;
case T_ExplainStmt:
{
ExplainStmt *n = (ExplainStmt *) parseTree;
result = makeNode(Query);
result->commandType = CMD_UTILITY;
n->query = transformStmt(pstate, (Node *) n->query,
extras_before, extras_after);
result->utilityStmt = (Node *) parseTree;
}
break;
case T_AlterTableStmt:
result = transformAlterTableStmt(pstate,
(AlterTableStmt *) parseTree,
extras_before, extras_after);
break;
case T_PrepareStmt:
result = transformPrepareStmt(pstate, (PrepareStmt *) parseTree);
break;
case T_ExecuteStmt:
result = transformExecuteStmt(pstate, (ExecuteStmt *) parseTree);
break;
/*
* Optimizable statements
*/
case T_InsertStmt:
result = transformInsertStmt(pstate, (InsertStmt *) parseTree,
extras_before, extras_after);
break;
case T_DeleteStmt:
result = transformDeleteStmt(pstate, (DeleteStmt *) parseTree);
break;
case T_UpdateStmt:
result = transformUpdateStmt(pstate, (UpdateStmt *) parseTree);
break;
case T_SelectStmt:
if (((SelectStmt *) parseTree)->op == SETOP_NONE)
result = transformSelectStmt(pstate,
(SelectStmt *) parseTree);
else
result = transformSetOperationStmt(pstate,
(SelectStmt *) parseTree);
break;
case T_DeclareCursorStmt:
result = transformDeclareCursorStmt(pstate,
(DeclareCursorStmt *) parseTree);
break;
default:
/*
* other statements don't require any transformation-- just return
* the original parsetree, yea!
*/
result = makeNode(Query);
result->commandType = CMD_UTILITY;
result->utilityStmt = (Node *) parseTree;
break;
}
/* Mark as original query until we learn differently */
result->querySource = QSRC_ORIGINAL;
result->canSetTag = true;
/*
* Check that we did not produce too many resnos; at the very least we
* cannot allow more than 2^16, since that would exceed the range of a
* AttrNumber. It seems safest to use MaxTupleAttributeNumber.
*/
if (pstate->p_next_resno - 1 > MaxTupleAttributeNumber)
ereport(ERROR,
(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
errmsg("target lists can have at most %d entries",
MaxTupleAttributeNumber)));
return result;
}
static Query *
transformViewStmt(ParseState *pstate, ViewStmt *stmt,
List **extras_before, List **extras_after)
{
Query *result = makeNode(Query);
result->commandType = CMD_UTILITY;
result->utilityStmt = (Node *) stmt;
stmt->query = transformStmt(pstate, (Node *) stmt->query,
extras_before, extras_after);
/*
* If a list of column names was given, run through and insert these into
* the actual query tree. - thomas 2000-03-08
*
* Outer loop is over targetlist to make it easier to skip junk targetlist
* entries.
*/
if (stmt->aliases != NIL)
{
ListCell *alist_item = list_head(stmt->aliases);
ListCell *targetList;
foreach(targetList, stmt->query->targetList)
{
TargetEntry *te = (TargetEntry *) lfirst(targetList);
Assert(IsA(te, TargetEntry));
/* junk columns don't get aliases */
if (te->resjunk)
continue;
te->resname = pstrdup(strVal(lfirst(alist_item)));
alist_item = lnext(alist_item);
if (alist_item == NULL)
break; /* done assigning aliases */
}
if (alist_item != NULL)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("CREATE VIEW specifies more column "
"names than columns")));
}
return result;
}
/*
* transformDeleteStmt -
* transforms a Delete Statement
*/
static Query *
transformDeleteStmt(ParseState *pstate, DeleteStmt *stmt)
{
Query *qry = makeNode(Query);
Node *qual;
qry->commandType = CMD_DELETE;
/* set up range table with just the result rel */
qry->resultRelation = setTargetTable(pstate, stmt->relation,
interpretInhOption(stmt->relation->inhOpt),
true,
ACL_DELETE);
qry->distinctClause = NIL;
/*
* The USING clause is non-standard SQL syntax, and is equivalent in
* functionality to the FROM list that can be specified for UPDATE. The
* USING keyword is used rather than FROM because FROM is already a
* keyword in the DELETE syntax.
*/
transformFromClause(pstate, stmt->usingClause);
/* fix where clause */
qual = transformWhereClause(pstate, stmt->whereClause, "WHERE");
/* done building the range table and jointree */
qry->rtable = pstate->p_rtable;
qry->jointree = makeFromExpr(pstate->p_joinlist, qual);
qry->hasSubLinks = pstate->p_hasSubLinks;
qry->hasAggs = pstate->p_hasAggs;
if (pstate->p_hasAggs)
parseCheckAggregates(pstate, qry);
return qry;
}
/*
* transformInsertStmt -
* transform an Insert Statement
*/
static Query *
transformInsertStmt(ParseState *pstate, InsertStmt *stmt,
List **extras_before, List **extras_after)
{
Query *qry = makeNode(Query);
Query *selectQuery = NULL;
List *sub_rtable;
List *sub_relnamespace;
List *sub_varnamespace;
List *icolumns;
List *attrnos;
ListCell *icols;
ListCell *attnos;
ListCell *tl;
qry->commandType = CMD_INSERT;
pstate->p_is_insert = true;
/*
* If a non-nil rangetable/namespace was passed in, and we are doing
* INSERT/SELECT, arrange to pass the rangetable/namespace down to the
* SELECT. This can only happen if we are inside a CREATE RULE, and in
* that case we want the rule's OLD and NEW rtable entries to appear as
* part of the SELECT's rtable, not as outer references for it. (Kluge!)
* The SELECT's joinlist is not affected however. We must do this before
* adding the target table to the INSERT's rtable.
*/
if (stmt->selectStmt)
{
sub_rtable = pstate->p_rtable;
pstate->p_rtable = NIL;
sub_relnamespace = pstate->p_relnamespace;
pstate->p_relnamespace = NIL;
sub_varnamespace = pstate->p_varnamespace;
pstate->p_varnamespace = NIL;
}
else
{
sub_rtable = NIL; /* not used, but keep compiler quiet */
sub_relnamespace = NIL;
sub_varnamespace = NIL;
}
/*
* Must get write lock on INSERT target table before scanning SELECT, else
* we will grab the wrong kind of initial lock if the target table is also
* mentioned in the SELECT part. Note that the target table is not added
* to the joinlist or namespace.
*/
qry->resultRelation = setTargetTable(pstate, stmt->relation,
false, false, ACL_INSERT);
/*
* Is it INSERT ... SELECT or INSERT ... VALUES?
*/
if (stmt->selectStmt)
{
/*
* We make the sub-pstate a child of the outer pstate so that it can
* see any Param definitions supplied from above. Since the outer
* pstate's rtable and namespace are presently empty, there are no
* side-effects of exposing names the sub-SELECT shouldn't be able to
* see.
*/
ParseState *sub_pstate = make_parsestate(pstate);
RangeTblEntry *rte;
RangeTblRef *rtr;
/*
* Process the source SELECT.
*
* It is important that this be handled just like a standalone SELECT;
* otherwise the behavior of SELECT within INSERT might be different
* from a stand-alone SELECT. (Indeed, Postgres up through 6.5 had
* bugs of just that nature...)
*/
sub_pstate->p_rtable = sub_rtable;
sub_pstate->p_relnamespace = sub_relnamespace;
sub_pstate->p_varnamespace = sub_varnamespace;
/*
* Note: we are not expecting that extras_before and extras_after are
* going to be used by the transformation of the SELECT statement.
*/
selectQuery = transformStmt(sub_pstate, stmt->selectStmt,
extras_before, extras_after);
release_pstate_resources(sub_pstate);
pfree(sub_pstate);
Assert(IsA(selectQuery, Query));
Assert(selectQuery->commandType == CMD_SELECT);
if (selectQuery->into)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("INSERT ... SELECT may not specify INTO")));
/*
* Make the source be a subquery in the INSERT's rangetable, and add
* it to the INSERT's joinlist.
*/
rte = addRangeTableEntryForSubquery(pstate,
selectQuery,
makeAlias("*SELECT*", NIL),
false);
rtr = makeNode(RangeTblRef);
/* assume new rte is at end */
rtr->rtindex = list_length(pstate->p_rtable);
Assert(rte == rt_fetch(rtr->rtindex, pstate->p_rtable));
pstate->p_joinlist = lappend(pstate->p_joinlist, rtr);
/*----------
* Generate a targetlist for the INSERT that selects all the
* non-resjunk columns from the subquery. (We need this to be
* separate from the subquery's tlist because we may add columns,
* insert datatype coercions, etc.)
*
* HACK: unknown-type constants and params in the SELECT's targetlist
* are copied up as-is rather than being referenced as subquery
* outputs. This is to ensure that when we try to coerce them to
* the target column's datatype, the right things happen (see
* special cases in coerce_type). Otherwise, this fails:
* INSERT INTO foo SELECT 'bar', ... FROM baz
*----------
*/
qry->targetList = NIL;
foreach(tl, selectQuery->targetList)
{
TargetEntry *tle = (TargetEntry *) lfirst(tl);
Expr *expr;
if (tle->resjunk)
continue;
if (tle->expr &&
(IsA(tle->expr, Const) ||IsA(tle->expr, Param)) &&
exprType((Node *) tle->expr) == UNKNOWNOID)
expr = tle->expr;
else
expr = (Expr *) makeVar(rtr->rtindex,
tle->resno,
exprType((Node *) tle->expr),
exprTypmod((Node *) tle->expr),
0);
tle = makeTargetEntry(expr,
(AttrNumber) pstate->p_next_resno++,
tle->resname,
false);
qry->targetList = lappend(qry->targetList, tle);
}
}
else
{
/*
* For INSERT ... VALUES, transform the given list of values to form a
* targetlist for the INSERT.
*/
qry->targetList = transformTargetList(pstate, stmt->targetList);
}
/*
* Now we are done with SELECT-like processing, and can get on with
* transforming the target list to match the INSERT target columns.
*/
/* Prepare to assign non-conflicting resnos to resjunk attributes */
if (pstate->p_next_resno <= pstate->p_target_relation->rd_rel->relnatts)
pstate->p_next_resno = pstate->p_target_relation->rd_rel->relnatts + 1;
/* Validate stmt->cols list, or build default list if no list given */
icolumns = checkInsertTargets(pstate, stmt->cols, &attrnos);
/*
* Prepare columns for assignment to target table.
*/
icols = list_head(icolumns);
attnos = list_head(attrnos);
foreach(tl, qry->targetList)
{
TargetEntry *tle = (TargetEntry *) lfirst(tl);
ResTarget *col;
if (icols == NULL || attnos == NULL)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("INSERT has more expressions than target columns")));
col = (ResTarget *) lfirst(icols);
Assert(IsA(col, ResTarget));
Assert(!tle->resjunk);
updateTargetListEntry(pstate, tle, col->name, lfirst_int(attnos),
col->indirection, col->location);
icols = lnext(icols);
attnos = lnext(attnos);
}
/*
* Ensure that the targetlist has the same number of entries that were
* present in the columns list. Don't do the check unless an explicit
* columns list was given, though.
*/
if (stmt->cols != NIL && (icols != NULL || attnos != NULL))
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("INSERT has more target columns than expressions")));
/* done building the range table and jointree */
qry->rtable = pstate->p_rtable;
qry->jointree = makeFromExpr(pstate->p_joinlist, NULL);
qry->hasSubLinks = pstate->p_hasSubLinks;
qry->hasAggs = pstate->p_hasAggs;
if (pstate->p_hasAggs)
parseCheckAggregates(pstate, qry);
return qry;
}
/*
* transformCreateStmt -
* transforms the "create table" statement
* SQL92 allows constraints to be scattered all over, so thumb through
* the columns and collect all constraints into one place.
* If there are any implied indices (e.g. UNIQUE or PRIMARY KEY)
* then expand those into multiple IndexStmt blocks.
* - thomas 1997-12-02
*/
static Query *
transformCreateStmt(ParseState *pstate, CreateStmt *stmt,
List **extras_before, List **extras_after)
{
CreateStmtContext cxt;
Query *q;
ListCell *elements;
cxt.stmtType = "CREATE TABLE";
cxt.relation = stmt->relation;
cxt.inhRelations = stmt->inhRelations;
cxt.isalter = false;
cxt.columns = NIL;
cxt.ckconstraints = NIL;
cxt.fkconstraints = NIL;
cxt.ixconstraints = NIL;
cxt.blist = NIL;
cxt.alist = NIL;
cxt.pkey = NULL;
cxt.hasoids = interpretOidsOption(stmt->hasoids);
/*
* Run through each primary element in the table creation clause. Separate
* column defs from constraints, and do preliminary analysis.
*/
foreach(elements, stmt->tableElts)
{
Node *element = lfirst(elements);
switch (nodeTag(element))
{
case T_ColumnDef:
transformColumnDefinition(pstate, &cxt,
(ColumnDef *) element);
break;
case T_Constraint:
transformTableConstraint(pstate, &cxt,
(Constraint *) element);
break;
case T_FkConstraint:
/* No pre-transformation needed */
cxt.fkconstraints = lappend(cxt.fkconstraints, element);
break;
case T_InhRelation:
transformInhRelation(pstate, &cxt,
(InhRelation *) element);
break;
default:
elog(ERROR, "unrecognized node type: %d",
(int) nodeTag(element));
break;
}
}
Assert(stmt->constraints == NIL);
/*
* Postprocess constraints that give rise to index definitions.
*/
transformIndexConstraints(pstate, &cxt);
/*
* Postprocess foreign-key constraints.
*/
transformFKConstraints(pstate, &cxt, true, false);
/*
* Output results.
*/
q = makeNode(Query);
q->commandType = CMD_UTILITY;
q->utilityStmt = (Node *) stmt;
stmt->tableElts = cxt.columns;
stmt->constraints = cxt.ckconstraints;
*extras_before = list_concat(*extras_before, cxt.blist);
*extras_after = list_concat(cxt.alist, *extras_after);
return q;
}
static void
transformColumnDefinition(ParseState *pstate, CreateStmtContext *cxt,
ColumnDef *column)
{
bool is_serial;
bool saw_nullable;
Constraint *constraint;
ListCell *clist;
cxt->columns = lappend(cxt->columns, column);
/* Check for SERIAL pseudo-types */
is_serial = false;
if (list_length(column->typename->names) == 1)
{
char *typname = strVal(linitial(column->typename->names));
if (strcmp(typname, "serial") == 0 ||
strcmp(typname, "serial4") == 0)
{
is_serial = true;
column->typename->names = NIL;
column->typename->typeid = INT4OID;
}
else if (strcmp(typname, "bigserial") == 0 ||
strcmp(typname, "serial8") == 0)
{
is_serial = true;
column->typename->names = NIL;
column->typename->typeid = INT8OID;
}
}
/* Do necessary work on the column type declaration */
transformColumnType(pstate, column);
/* Special actions for SERIAL pseudo-types */
if (is_serial)
{
Oid snamespaceid;
char *snamespace;
char *sname;
char *qstring;
A_Const *snamenode;
FuncCall *funccallnode;
CreateSeqStmt *seqstmt;
/*
* Determine namespace and name to use for the sequence.
*
* Although we use ChooseRelationName, it's not guaranteed that the
* selected sequence name won't conflict; given sufficiently long
* field names, two different serial columns in the same table could
* be assigned the same sequence name, and we'd not notice since we
* aren't creating the sequence quite yet. In practice this seems
* quite unlikely to be a problem, especially since few people would
* need two serial columns in one table.
*/
snamespaceid = RangeVarGetCreationNamespace(cxt->relation);
snamespace = get_namespace_name(snamespaceid);
sname = ChooseRelationName(cxt->relation->relname,
column->colname,
"seq",
snamespaceid);
ereport(NOTICE,
(errmsg("%s will create implicit sequence \"%s\" for serial column \"%s.%s\"",
cxt->stmtType, sname,
cxt->relation->relname, column->colname)));
/*
* Build a CREATE SEQUENCE command to create the sequence object, and
* add it to the list of things to be done before this CREATE/ALTER
* TABLE.
*/
seqstmt = makeNode(CreateSeqStmt);
seqstmt->sequence = makeRangeVar(snamespace, sname);
seqstmt->options = NIL;
cxt->blist = lappend(cxt->blist, seqstmt);
/*
* Mark the ColumnDef so that during execution, an appropriate
* dependency will be added from the sequence to the column.
*/
column->support = makeRangeVar(snamespace, sname);
/*
* Create appropriate constraints for SERIAL. We do this in full,
* rather than shortcutting, so that we will detect any conflicting
* constraints the user wrote (like a different DEFAULT).
*
* Create an expression tree representing the function call
* nextval('sequencename'). We cannot reduce the raw tree to cooked
* form until after the sequence is created, but there's no need to do
* so.
*/
qstring = quote_qualified_identifier(snamespace, sname);
snamenode = makeNode(A_Const);
snamenode->val.type = T_String;
snamenode->val.val.str = qstring;
snamenode->typename = SystemTypeName("regclass");
funccallnode = makeNode(FuncCall);
funccallnode->funcname = SystemFuncName("nextval");
funccallnode->args = list_make1(snamenode);
funccallnode->agg_star = false;
funccallnode->agg_distinct = false;
funccallnode->location = -1;
constraint = makeNode(Constraint);
constraint->contype = CONSTR_DEFAULT;
constraint->raw_expr = (Node *) funccallnode;
constraint->cooked_expr = NULL;
constraint->keys = NIL;
column->constraints = lappend(column->constraints, constraint);
constraint = makeNode(Constraint);
constraint->contype = CONSTR_NOTNULL;
column->constraints = lappend(column->constraints, constraint);
}
/* Process column constraints, if any... */
transformConstraintAttrs(column->constraints);
saw_nullable = false;
foreach(clist, column->constraints)
{
constraint = lfirst(clist);
/*
* If this column constraint is a FOREIGN KEY constraint, then we fill
* in the current attribute's name and throw it into the list of FK
* constraints to be processed later.
*/
if (IsA(constraint, FkConstraint))
{
FkConstraint *fkconstraint = (FkConstraint *) constraint;
fkconstraint->fk_attrs = list_make1(makeString(column->colname));
cxt->fkconstraints = lappend(cxt->fkconstraints, fkconstraint);
continue;
}
Assert(IsA(constraint, Constraint));
switch (constraint->contype)
{
case CONSTR_NULL:
if (saw_nullable && column->is_not_null)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("conflicting NULL/NOT NULL declarations for column \"%s\" of table \"%s\"",
column->colname, cxt->relation->relname)));
column->is_not_null = FALSE;
saw_nullable = true;
break;
case CONSTR_NOTNULL:
if (saw_nullable && !column->is_not_null)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("conflicting NULL/NOT NULL declarations for column \"%s\" of table \"%s\"",
column->colname, cxt->relation->relname)));
column->is_not_null = TRUE;
saw_nullable = true;
break;
case CONSTR_DEFAULT:
if (column->raw_default != NULL)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("multiple default values specified for column \"%s\" of table \"%s\"",
column->colname, cxt->relation->relname)));
column->raw_default = constraint->raw_expr;
Assert(constraint->cooked_expr == NULL);
break;
case CONSTR_PRIMARY:
case CONSTR_UNIQUE:
if (constraint->keys == NIL)
constraint->keys = list_make1(makeString(column->colname));
cxt->ixconstraints = lappend(cxt->ixconstraints, constraint);
break;
case CONSTR_CHECK:
cxt->ckconstraints = lappend(cxt->ckconstraints, constraint);
break;
case CONSTR_ATTR_DEFERRABLE:
case CONSTR_ATTR_NOT_DEFERRABLE:
case CONSTR_ATTR_DEFERRED:
case CONSTR_ATTR_IMMEDIATE:
/* transformConstraintAttrs took care of these */
break;
default:
elog(ERROR, "unrecognized constraint type: %d",
constraint->contype);
break;
}
}
}
static void
transformTableConstraint(ParseState *pstate, CreateStmtContext *cxt,
Constraint *constraint)
{
switch (constraint->contype)
{
case CONSTR_PRIMARY:
case CONSTR_UNIQUE:
cxt->ixconstraints = lappend(cxt->ixconstraints, constraint);
break;
case CONSTR_CHECK:
cxt->ckconstraints = lappend(cxt->ckconstraints, constraint);
break;
case CONSTR_NULL:
case CONSTR_NOTNULL:
case CONSTR_DEFAULT:
case CONSTR_ATTR_DEFERRABLE:
case CONSTR_ATTR_NOT_DEFERRABLE:
case CONSTR_ATTR_DEFERRED:
case CONSTR_ATTR_IMMEDIATE:
elog(ERROR, "invalid context for constraint type %d",
constraint->contype);
break;
default:
elog(ERROR, "unrecognized constraint type: %d",
constraint->contype);
break;
}
}
/*
* transformInhRelation
*
* Change the LIKE <subtable> portion of a CREATE TABLE statement into the
* column definitions which recreate the user defined column portions of <subtable>.
*/
static void
transformInhRelation(ParseState *pstate, CreateStmtContext *cxt,
InhRelation *inhRelation)
{
AttrNumber parent_attno;
Relation relation;
TupleDesc tupleDesc;
TupleConstr *constr;
AclResult aclresult;
relation = heap_openrv(inhRelation->relation, AccessShareLock);
if (relation->rd_rel->relkind != RELKIND_RELATION)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("inherited relation \"%s\" is not a table",
inhRelation->relation->relname)));
/*
* Check for SELECT privilages
*/
aclresult = pg_class_aclcheck(RelationGetRelid(relation), GetUserId(),
ACL_SELECT);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, ACL_KIND_CLASS,
RelationGetRelationName(relation));
tupleDesc = RelationGetDescr(relation);
constr = tupleDesc->constr;
/*
* Insert the inherited attributes into the cxt for the new table
* definition.
*/
for (parent_attno = 1; parent_attno <= tupleDesc->natts;
parent_attno++)
{
Form_pg_attribute attribute = tupleDesc->attrs[parent_attno - 1];
char *attributeName = NameStr(attribute->attname);
ColumnDef *def;
/*
* Ignore dropped columns in the parent.
*/
if (attribute->attisdropped)
continue;
/*
* Create a new inherited column.
*
* For constraints, ONLY the NOT NULL constraint is inherited by the
* new column definition per SQL99.
*/
def = makeNode(ColumnDef);
def->colname = pstrdup(attributeName);
def->typename = makeTypeNameFromOid(attribute->atttypid,
attribute->atttypmod);
def->inhcount = 0;
def->is_local = false;
def->is_not_null = attribute->attnotnull;
def->raw_default = NULL;
def->cooked_default = NULL;
def->constraints = NIL;
def->support = NULL;
/*
* Add to column list
*/
cxt->columns = lappend(cxt->columns, def);
/*
* Copy default if any, and the default has been requested
*/
if (attribute->atthasdef && inhRelation->including_defaults)
{
char *this_default = NULL;
AttrDefault *attrdef;
int i;
/* Find default in constraint structure */
Assert(constr != NULL);
attrdef = constr->defval;
for (i = 0; i < constr->num_defval; i++)
{
if (attrdef[i].adnum == parent_attno)
{
this_default = attrdef[i].adbin;
break;
}
}
Assert(this_default != NULL);
/*
* If default expr could contain any vars, we'd need to fix 'em,
* but it can't; so default is ready to apply to child.
*/
def->cooked_default = pstrdup(this_default);
}
}
/*
* Close the parent rel, but keep our AccessShareLock on it until xact
* commit. That will prevent someone else from deleting or ALTERing the
* parent before the child is committed.
*/
heap_close(relation, NoLock);
}
static void
transformIndexConstraints(ParseState *pstate, CreateStmtContext *cxt)
{
IndexStmt *index;
List *indexlist = NIL;
ListCell *listptr;
ListCell *l;
/*
* Run through the constraints that need to generate an index. For PRIMARY
* KEY, mark each column as NOT NULL and create an index. For UNIQUE,
* create an index as for PRIMARY KEY, but do not insist on NOT NULL.
*/
foreach(listptr, cxt->ixconstraints)
{
Constraint *constraint = lfirst(listptr);
ListCell *keys;
IndexElem *iparam;
Assert(IsA(constraint, Constraint));
Assert((constraint->contype == CONSTR_PRIMARY)
|| (constraint->contype == CONSTR_UNIQUE));
index = makeNode(IndexStmt);
index->unique = true;
index->primary = (constraint->contype == CONSTR_PRIMARY);
if (index->primary)
{
if (cxt->pkey != NULL)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("multiple primary keys for table \"%s\" are not allowed",
cxt->relation->relname)));
cxt->pkey = index;
/*
* In ALTER TABLE case, a primary index might already exist, but
* DefineIndex will check for it.
*/
}
index->isconstraint = true;
if (constraint->name != NULL)
index->idxname = pstrdup(constraint->name);
else
index->idxname = NULL; /* DefineIndex will choose name */
index->relation = cxt->relation;
index->accessMethod = DEFAULT_INDEX_TYPE;
index->tableSpace = constraint->indexspace;
index->indexParams = NIL;
index->whereClause = NULL;
/*
* Make sure referenced keys exist. If we are making a PRIMARY KEY
* index, also make sure they are NOT NULL, if possible. (Although we
* could leave it to DefineIndex to mark the columns NOT NULL, it's
* more efficient to get it right the first time.)
*/
foreach(keys, constraint->keys)
{
char *key = strVal(lfirst(keys));
bool found = false;
ColumnDef *column = NULL;
ListCell *columns;
foreach(columns, cxt->columns)
{
column = (ColumnDef *) lfirst(columns);
Assert(IsA(column, ColumnDef));
if (strcmp(column->colname, key) == 0)
{
found = true;
break;
}
}
if (found)
{
/* found column in the new table; force it to be NOT NULL */
if (constraint->contype == CONSTR_PRIMARY)
column->is_not_null = TRUE;
}
else if (SystemAttributeByName(key, cxt->hasoids) != NULL)
{
/*
* column will be a system column in the new table, so accept
* it. System columns can't ever be null, so no need to worry
* about PRIMARY/NOT NULL constraint.
*/
found = true;
}
else if (cxt->inhRelations)
{
/* try inherited tables */
ListCell *inher;
foreach(inher, cxt->inhRelations)
{
RangeVar *inh = (RangeVar *) lfirst(inher);
Relation rel;
int count;
Assert(IsA(inh, RangeVar));
rel = heap_openrv(inh, AccessShareLock);
if (rel->rd_rel->relkind != RELKIND_RELATION)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("inherited relation \"%s\" is not a table",
inh->relname)));
for (count = 0; count < rel->rd_att->natts; count++)
{
Form_pg_attribute inhattr = rel->rd_att->attrs[count];
char *inhname = NameStr(inhattr->attname);
if (inhattr->attisdropped)
continue;
if (strcmp(key, inhname) == 0)
{
found = true;
/*
* We currently have no easy way to force an
* inherited column to be NOT NULL at creation, if
* its parent wasn't so already. We leave it to
* DefineIndex to fix things up in this case.
*/
break;
}
}
heap_close(rel, NoLock);
if (found)
break;
}
}
/*
* In the ALTER TABLE case, don't complain about index keys not
* created in the command; they may well exist already.
* DefineIndex will complain about them if not, and will also take
* care of marking them NOT NULL.
*/
if (!found && !cxt->isalter)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_COLUMN),
errmsg("column \"%s\" named in key does not exist",
key)));
/* Check for PRIMARY KEY(foo, foo) */
foreach(columns, index->indexParams)
{
iparam = (IndexElem *) lfirst(columns);
if (iparam->name && strcmp(key, iparam->name) == 0)
{
if (index->primary)
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_COLUMN),
errmsg("column \"%s\" appears twice in primary key constraint",
key)));
else
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_COLUMN),
errmsg("column \"%s\" appears twice in unique constraint",
key)));
}
}
/* OK, add it to the index definition */
iparam = makeNode(IndexElem);
iparam->name = pstrdup(key);
iparam->expr = NULL;
iparam->opclass = NIL;
index->indexParams = lappend(index->indexParams, iparam);
}
indexlist = lappend(indexlist, index);
}
/*
* Scan the index list and remove any redundant index specifications. This
* can happen if, for instance, the user writes UNIQUE PRIMARY KEY. A
* strict reading of SQL92 would suggest raising an error instead, but
* that strikes me as too anal-retentive. - tgl 2001-02-14
*
* XXX in ALTER TABLE case, it'd be nice to look for duplicate
* pre-existing indexes, too.
*/
cxt->alist = NIL;
if (cxt->pkey != NULL)
{
/* Make sure we keep the PKEY index in preference to others... */
cxt->alist = list_make1(cxt->pkey);
}
foreach(l, indexlist)
{
bool keep = true;
ListCell *k;
index = lfirst(l);
/* if it's pkey, it's already in cxt->alist */
if (index == cxt->pkey)
continue;
foreach(k, cxt->alist)
{
IndexStmt *priorindex = lfirst(k);
if (equal(index->indexParams, priorindex->indexParams))
{
/*
* If the prior index is as yet unnamed, and this one is
* named, then transfer the name to the prior index. This
* ensures that if we have named and unnamed constraints,
* we'll use (at least one of) the names for the index.
*/
if (priorindex->idxname == NULL)
priorindex->idxname = index->idxname;
keep = false;
break;
}
}
if (keep)
cxt->alist = lappend(cxt->alist, index);
}
}
static void
transformFKConstraints(ParseState *pstate, CreateStmtContext *cxt,
bool skipValidation, bool isAddConstraint)
{
ListCell *fkclist;
if (cxt->fkconstraints == NIL)
return;
/*
* If CREATE TABLE or adding a column with NULL default, we can safely
* skip validation of the constraint.
*/
if (skipValidation)
{
foreach(fkclist, cxt->fkconstraints)
{
FkConstraint *fkconstraint = (FkConstraint *) lfirst(fkclist);
fkconstraint->skip_validation = true;
}
}
/*
* For CREATE TABLE or ALTER TABLE ADD COLUMN, gin up an ALTER TABLE ADD
* CONSTRAINT command to execute after the basic command is complete. (If
* called from ADD CONSTRAINT, that routine will add the FK constraints to
* its own subcommand list.)
*
* Note: the ADD CONSTRAINT command must also execute after any index
* creation commands. Thus, this should run after
* transformIndexConstraints, so that the CREATE INDEX commands are
* already in cxt->alist.
*/
if (!isAddConstraint)
{
AlterTableStmt *alterstmt = makeNode(AlterTableStmt);
alterstmt->relation = cxt->relation;
alterstmt->cmds = NIL;
alterstmt->relkind = OBJECT_TABLE;
foreach(fkclist, cxt->fkconstraints)
{
FkConstraint *fkconstraint = (FkConstraint *) lfirst(fkclist);
AlterTableCmd *altercmd = makeNode(AlterTableCmd);
altercmd->subtype = AT_ProcessedConstraint;
altercmd->name = NULL;
altercmd->def = (Node *) fkconstraint;
alterstmt->cmds = lappend(alterstmt->cmds, altercmd);
}
cxt->alist = lappend(cxt->alist, alterstmt);
}
}
/*
* transformIndexStmt -
* transforms the qualification of the index statement
*/
static Query *
transformIndexStmt(ParseState *pstate, IndexStmt *stmt)
{
Query *qry;
RangeTblEntry *rte = NULL;
ListCell *l;
qry = makeNode(Query);
qry->commandType = CMD_UTILITY;
/* take care of the where clause */
if (stmt->whereClause)
{
/*
* Put the parent table into the rtable so that the WHERE clause can
* refer to its fields without qualification. Note that this only
* works if the parent table already exists --- so we can't easily
* support predicates on indexes created implicitly by CREATE TABLE.
* Fortunately, that's not necessary.
*/
rte = addRangeTableEntry(pstate, stmt->relation, NULL, false, true);
/* no to join list, yes to namespaces */
addRTEtoQuery(pstate, rte, false, true, true);
stmt->whereClause = transformWhereClause(pstate, stmt->whereClause,
"WHERE");
}
/* take care of any index expressions */
foreach(l, stmt->indexParams)
{
IndexElem *ielem = (IndexElem *) lfirst(l);
if (ielem->expr)
{
/* Set up rtable as for predicate, see notes above */
if (rte == NULL)
{
rte = addRangeTableEntry(pstate, stmt->relation, NULL,
false, true);
/* no to join list, yes to namespaces */
addRTEtoQuery(pstate, rte, false, true, true);
}
ielem->expr = transformExpr(pstate, ielem->expr);
/*
* We check only that the result type is legitimate; this is for
* consistency with what transformWhereClause() checks for the
* predicate. DefineIndex() will make more checks.
*/
if (expression_returns_set(ielem->expr))
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("index expression may not return a set")));
}
}
qry->hasSubLinks = pstate->p_hasSubLinks;
stmt->rangetable = pstate->p_rtable;
qry->utilityStmt = (Node *) stmt;
return qry;
}
/*
* transformRuleStmt -
* transform a Create Rule Statement. The actions is a list of parse
* trees which is transformed into a list of query trees.
*/
static Query *
transformRuleStmt(ParseState *pstate, RuleStmt *stmt,
List **extras_before, List **extras_after)
{
Query *qry;
Relation rel;
RangeTblEntry *oldrte;
RangeTblEntry *newrte;
qry = makeNode(Query);
qry->commandType = CMD_UTILITY;
qry->utilityStmt = (Node *) stmt;
/*
* To avoid deadlock, make sure the first thing we do is grab
* AccessExclusiveLock on the target relation. This will be needed by
* DefineQueryRewrite(), and we don't want to grab a lesser lock
* beforehand.
*/
rel = heap_openrv(stmt->relation, AccessExclusiveLock);
/*
* NOTE: 'OLD' must always have a varno equal to 1 and 'NEW' equal to 2.
* Set up their RTEs in the main pstate for use in parsing the rule
* qualification.
*/
Assert(pstate->p_rtable == NIL);
oldrte = addRangeTableEntryForRelation(pstate, rel,
makeAlias("*OLD*", NIL),
false, false);
newrte = addRangeTableEntryForRelation(pstate, rel,
makeAlias("*NEW*", NIL),
false, false);
/* Must override addRangeTableEntry's default access-check flags */
oldrte->requiredPerms = 0;
newrte->requiredPerms = 0;
/*
* They must be in the namespace too for lookup purposes, but only add the
* one(s) that are relevant for the current kind of rule. In an UPDATE
* rule, quals must refer to OLD.field or NEW.field to be unambiguous, but
* there's no need to be so picky for INSERT & DELETE. We do not add them
* to the joinlist.
*/
switch (stmt->event)
{
case CMD_SELECT:
addRTEtoQuery(pstate, oldrte, false, true, true);
break;
case CMD_UPDATE:
addRTEtoQuery(pstate, oldrte, false, true, true);
addRTEtoQuery(pstate, newrte, false, true, true);
break;
case CMD_INSERT:
addRTEtoQuery(pstate, newrte, false, true, true);
break;
case CMD_DELETE:
addRTEtoQuery(pstate, oldrte, false, true, true);
break;
default:
elog(ERROR, "unrecognized event type: %d",
(int) stmt->event);
break;
}
/* take care of the where clause */
stmt->whereClause = transformWhereClause(pstate, stmt->whereClause,
"WHERE");
if (list_length(pstate->p_rtable) != 2) /* naughty, naughty... */
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("rule WHERE condition may not contain references to other relations")));
/* aggregates not allowed (but subselects are okay) */
if (pstate->p_hasAggs)
ereport(ERROR,
(errcode(ERRCODE_GROUPING_ERROR),
errmsg("cannot use aggregate function in rule WHERE condition")));
/* save info about sublinks in where clause */
qry->hasSubLinks = pstate->p_hasSubLinks;
/*
* 'instead nothing' rules with a qualification need a query rangetable so
* the rewrite handler can add the negated rule qualification to the
* original query. We create a query with the new command type CMD_NOTHING
* here that is treated specially by the rewrite system.
*/
if (stmt->actions == NIL)
{
Query *nothing_qry = makeNode(Query);
nothing_qry->commandType = CMD_NOTHING;
nothing_qry->rtable = pstate->p_rtable;
nothing_qry->jointree = makeFromExpr(NIL, NULL); /* no join wanted */
stmt->actions = list_make1(nothing_qry);
}
else
{
ListCell *l;
List *newactions = NIL;
/*
* transform each statement, like parse_sub_analyze()
*/
foreach(l, stmt->actions)
{
Node *action = (Node *) lfirst(l);
ParseState *sub_pstate = make_parsestate(pstate->parentParseState);
Query *sub_qry,
*top_subqry;
bool has_old,
has_new;
/*
* Set up OLD/NEW in the rtable for this statement. The entries
* are added only to relnamespace, not varnamespace, because we
* don't want them to be referred to by unqualified field names
* nor "*" in the rule actions. We decide later whether to put
* them in the joinlist.
*/
oldrte = addRangeTableEntryForRelation(sub_pstate, rel,
makeAlias("*OLD*", NIL),
false, false);
newrte = addRangeTableEntryForRelation(sub_pstate, rel,
makeAlias("*NEW*", NIL),
false, false);
oldrte->requiredPerms = 0;
newrte->requiredPerms = 0;
addRTEtoQuery(sub_pstate, oldrte, false, true, false);
addRTEtoQuery(sub_pstate, newrte, false, true, false);
/* Transform the rule action statement */
top_subqry = transformStmt(sub_pstate, action,
extras_before, extras_after);
/*
* We cannot support utility-statement actions (eg NOTIFY) with
* nonempty rule WHERE conditions, because there's no way to make
* the utility action execute conditionally.
*/
if (top_subqry->commandType == CMD_UTILITY &&
stmt->whereClause != NULL)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("rules with WHERE conditions may only have SELECT, INSERT, UPDATE, or DELETE actions")));
/*
* If the action is INSERT...SELECT, OLD/NEW have been pushed down
* into the SELECT, and that's what we need to look at. (Ugly
* kluge ... try to fix this when we redesign querytrees.)
*/
sub_qry = getInsertSelectQuery(top_subqry, NULL);
/*
* If the sub_qry is a setop, we cannot attach any qualifications
* to it, because the planner won't notice them. This could
* perhaps be relaxed someday, but for now, we may as well reject
* such a rule immediately.
*/
if (sub_qry->setOperations != NULL && stmt->whereClause != NULL)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("conditional UNION/INTERSECT/EXCEPT statements are not implemented")));
/*
* Validate action's use of OLD/NEW, qual too
*/
has_old =
rangeTableEntry_used((Node *) sub_qry, PRS2_OLD_VARNO, 0) ||
rangeTableEntry_used(stmt->whereClause, PRS2_OLD_VARNO, 0);
has_new =
rangeTableEntry_used((Node *) sub_qry, PRS2_NEW_VARNO, 0) ||
rangeTableEntry_used(stmt->whereClause, PRS2_NEW_VARNO, 0);
switch (stmt->event)
{
case CMD_SELECT:
if (has_old)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("ON SELECT rule may not use OLD")));
if (has_new)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("ON SELECT rule may not use NEW")));
break;
case CMD_UPDATE:
/* both are OK */
break;
case CMD_INSERT:
if (has_old)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("ON INSERT rule may not use OLD")));
break;
case CMD_DELETE:
if (has_new)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("ON DELETE rule may not use NEW")));
break;
default:
elog(ERROR, "unrecognized event type: %d",
(int) stmt->event);
break;
}
/*
* For efficiency's sake, add OLD to the rule action's jointree
* only if it was actually referenced in the statement or qual.
*
* For INSERT, NEW is not really a relation (only a reference to
* the to-be-inserted tuple) and should never be added to the
* jointree.
*
* For UPDATE, we treat NEW as being another kind of reference to
* OLD, because it represents references to *transformed* tuples
* of the existing relation. It would be wrong to enter NEW
* separately in the jointree, since that would cause a double
* join of the updated relation. It's also wrong to fail to make
* a jointree entry if only NEW and not OLD is mentioned.
*/
if (has_old || (has_new && stmt->event == CMD_UPDATE))
{
/*
* If sub_qry is a setop, manipulating its jointree will do no
* good at all, because the jointree is dummy. (This should be
* a can't-happen case because of prior tests.)
*/
if (sub_qry->setOperations != NULL)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("conditional UNION/INTERSECT/EXCEPT statements are not implemented")));
/* hack so we can use addRTEtoQuery() */
sub_pstate->p_rtable = sub_qry->rtable;
sub_pstate->p_joinlist = sub_qry->jointree->fromlist;
addRTEtoQuery(sub_pstate, oldrte, true, false, false);
sub_qry->jointree->fromlist = sub_pstate->p_joinlist;
}
newactions = lappend(newactions, top_subqry);
release_pstate_resources(sub_pstate);
pfree(sub_pstate);
}
stmt->actions = newactions;
}
/* Close relation, but keep the exclusive lock */
heap_close(rel, NoLock);
return qry;
}
/*
* transformSelectStmt -
* transforms a Select Statement
*
* Note: this is also used for DECLARE CURSOR statements.
*/
static Query *
transformSelectStmt(ParseState *pstate, SelectStmt *stmt)
{
Query *qry = makeNode(Query);
Node *qual;
ListCell *l;
qry->commandType = CMD_SELECT;
/* make FOR UPDATE/FOR SHARE info available to addRangeTableEntry */
pstate->p_locking_clause = stmt->lockingClause;
/* process the FROM clause */
transformFromClause(pstate, stmt->fromClause);
/* transform targetlist */
qry->targetList = transformTargetList(pstate, stmt->targetList);
/* handle any SELECT INTO/CREATE TABLE AS spec */
qry->into = stmt->into;
if (stmt->intoColNames)
applyColumnNames(qry->targetList, stmt->intoColNames);
qry->intoHasOids = interpretOidsOption(stmt->intoHasOids);
qry->intoOnCommit = stmt->intoOnCommit;
qry->intoTableSpaceName = stmt->intoTableSpaceName;
/* mark column origins */
markTargetListOrigins(pstate, qry->targetList);
/* transform WHERE */
qual = transformWhereClause(pstate, stmt->whereClause, "WHERE");
/*
* Initial processing of HAVING clause is just like WHERE clause.
*/
qry->havingQual = transformWhereClause(pstate, stmt->havingClause,
"HAVING");
/*
* Transform sorting/grouping stuff. Do ORDER BY first because both
* transformGroupClause and transformDistinctClause need the results.
*/
qry->sortClause = transformSortClause(pstate,
stmt->sortClause,
&qry->targetList,
true /* fix unknowns */ );
qry->groupClause = transformGroupClause(pstate,
stmt->groupClause,
&qry->targetList,
qry->sortClause);
qry->distinctClause = transformDistinctClause(pstate,
stmt->distinctClause,
&qry->targetList,
&qry->sortClause);
qry->limitOffset = transformLimitClause(pstate, stmt->limitOffset,
"OFFSET");
qry->limitCount = transformLimitClause(pstate, stmt->limitCount,
"LIMIT");
qry->rtable = pstate->p_rtable;
qry->jointree = makeFromExpr(pstate->p_joinlist, qual);
qry->hasSubLinks = pstate->p_hasSubLinks;
qry->hasAggs = pstate->p_hasAggs;
if (pstate->p_hasAggs || qry->groupClause || qry->havingQual)
parseCheckAggregates(pstate, qry);
foreach(l, stmt->lockingClause)
{
transformLockingClause(qry, (LockingClause *) lfirst(l));
}
return qry;
}
/*
* transformSetOperationsStmt -
* transforms a set-operations tree
*
* A set-operation tree is just a SELECT, but with UNION/INTERSECT/EXCEPT
* structure to it. We must transform each leaf SELECT and build up a top-
* level Query that contains the leaf SELECTs as subqueries in its rangetable.
* The tree of set operations is converted into the setOperations field of
* the top-level Query.
*/
static Query *
transformSetOperationStmt(ParseState *pstate, SelectStmt *stmt)
{
Query *qry = makeNode(Query);
SelectStmt *leftmostSelect;
int leftmostRTI;
Query *leftmostQuery;
SetOperationStmt *sostmt;
RangeVar *into;
List *intoColNames;
List *sortClause;
Node *limitOffset;
Node *limitCount;
List *lockingClause;
Node *node;
ListCell *left_tlist,
*dtlist,
*l;
List *targetvars,
*targetnames,
*sv_relnamespace,
*sv_varnamespace,
*sv_rtable;
RangeTblEntry *jrte;
int tllen;
qry->commandType = CMD_SELECT;
/*
* Find leftmost leaf SelectStmt; extract the one-time-only items from it
* and from the top-level node.
*/
leftmostSelect = stmt->larg;
while (leftmostSelect && leftmostSelect->op != SETOP_NONE)
leftmostSelect = leftmostSelect->larg;
Assert(leftmostSelect && IsA(leftmostSelect, SelectStmt) &&
leftmostSelect->larg == NULL);
into = leftmostSelect->into;
intoColNames = leftmostSelect->intoColNames;
/* clear them to prevent complaints in transformSetOperationTree() */
leftmostSelect->into = NULL;
leftmostSelect->intoColNames = NIL;
/*
* These are not one-time, exactly, but we want to process them here and
* not let transformSetOperationTree() see them --- else it'll just
* recurse right back here!
*/
sortClause = stmt->sortClause;
limitOffset = stmt->limitOffset;
limitCount = stmt->limitCount;
lockingClause = stmt->lockingClause;
stmt->sortClause = NIL;
stmt->limitOffset = NULL;
stmt->limitCount = NULL;
stmt->lockingClause = NIL;
/* We don't support FOR UPDATE/SHARE with set ops at the moment. */
if (lockingClause)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SELECT FOR UPDATE/SHARE is not allowed with UNION/INTERSECT/EXCEPT")));
/*
* Recursively transform the components of the tree.
*/
sostmt = (SetOperationStmt *) transformSetOperationTree(pstate, stmt);
Assert(sostmt && IsA(sostmt, SetOperationStmt));
qry->setOperations = (Node *) sostmt;
/*
* Re-find leftmost SELECT (now it's a sub-query in rangetable)
*/
node = sostmt->larg;
while (node && IsA(node, SetOperationStmt))
node = ((SetOperationStmt *) node)->larg;
Assert(node && IsA(node, RangeTblRef));
leftmostRTI = ((RangeTblRef *) node)->rtindex;
leftmostQuery = rt_fetch(leftmostRTI, pstate->p_rtable)->subquery;
Assert(leftmostQuery != NULL);
/*
* Generate dummy targetlist for outer query using column names of
* leftmost select and common datatypes of topmost set operation. Also
* make lists of the dummy vars and their names for use in parsing ORDER
* BY.
*
* Note: we use leftmostRTI as the varno of the dummy variables. It
* shouldn't matter too much which RT index they have, as long as they
* have one that corresponds to a real RT entry; else funny things may
* happen when the tree is mashed by rule rewriting.
*/
qry->targetList = NIL;
targetvars = NIL;
targetnames = NIL;
left_tlist = list_head(leftmostQuery->targetList);
foreach(dtlist, sostmt->colTypes)
{
Oid colType = lfirst_oid(dtlist);
TargetEntry *lefttle = (TargetEntry *) lfirst(left_tlist);
char *colName;
TargetEntry *tle;
Expr *expr;
Assert(!lefttle->resjunk);
colName = pstrdup(lefttle->resname);
expr = (Expr *) makeVar(leftmostRTI,
lefttle->resno,
colType,
-1,
0);
tle = makeTargetEntry(expr,
(AttrNumber) pstate->p_next_resno++,
colName,
false);
qry->targetList = lappend(qry->targetList, tle);
targetvars = lappend(targetvars, expr);
targetnames = lappend(targetnames, makeString(colName));
left_tlist = lnext(left_tlist);
}
/*
* Handle SELECT INTO/CREATE TABLE AS.
*
* Any column names from CREATE TABLE AS need to be attached to both the
* top level and the leftmost subquery. We do not do this earlier because
* we do *not* want the targetnames list to be affected.
*/
qry->into = into;
if (intoColNames)
{
applyColumnNames(qry->targetList, intoColNames);
applyColumnNames(leftmostQuery->targetList, intoColNames);
}
/*
* As a first step towards supporting sort clauses that are expressions
* using the output columns, generate a varnamespace entry that makes the
* output columns visible. A Join RTE node is handy for this, since we
* can easily control the Vars generated upon matches.
*
* Note: we don't yet do anything useful with such cases, but at least
* "ORDER BY upper(foo)" will draw the right error message rather than
* "foo not found".
*/
jrte = addRangeTableEntryForJoin(NULL,
targetnames,
JOIN_INNER,
targetvars,
NULL,
false);
sv_rtable = pstate->p_rtable;
pstate->p_rtable = list_make1(jrte);
sv_relnamespace = pstate->p_relnamespace;
pstate->p_relnamespace = NIL; /* no qualified names allowed */
sv_varnamespace = pstate->p_varnamespace;
pstate->p_varnamespace = list_make1(jrte);
/*
* For now, we don't support resjunk sort clauses on the output of a
* setOperation tree --- you can only use the SQL92-spec options of
* selecting an output column by name or number. Enforce by checking that
* transformSortClause doesn't add any items to tlist.
*/
tllen = list_length(qry->targetList);
qry->sortClause = transformSortClause(pstate,
sortClause,
&qry->targetList,
false /* no unknowns expected */ );
pstate->p_rtable = sv_rtable;
pstate->p_relnamespace = sv_relnamespace;
pstate->p_varnamespace = sv_varnamespace;
if (tllen != list_length(qry->targetList))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("ORDER BY on a UNION/INTERSECT/EXCEPT result must be on one of the result columns")));
qry->limitOffset = transformLimitClause(pstate, limitOffset,
"OFFSET");
qry->limitCount = transformLimitClause(pstate, limitCount,
"LIMIT");
qry->rtable = pstate->p_rtable;
qry->jointree = makeFromExpr(pstate->p_joinlist, NULL);
qry->hasSubLinks = pstate->p_hasSubLinks;
qry->hasAggs = pstate->p_hasAggs;
if (pstate->p_hasAggs || qry->groupClause || qry->havingQual)
parseCheckAggregates(pstate, qry);
foreach(l, lockingClause)
{
transformLockingClause(qry, (LockingClause *) lfirst(l));
}
return qry;
}
/*
* transformSetOperationTree
* Recursively transform leaves and internal nodes of a set-op tree
*/
static Node *
transformSetOperationTree(ParseState *pstate, SelectStmt *stmt)
{
bool isLeaf;
Assert(stmt && IsA(stmt, SelectStmt));
/*
* Validity-check both leaf and internal SELECTs for disallowed ops.
*/
if (stmt->into)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("INTO is only allowed on first SELECT of UNION/INTERSECT/EXCEPT")));
/* We don't support FOR UPDATE/SHARE with set ops at the moment. */
if (stmt->lockingClause)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SELECT FOR UPDATE/SHARE is not allowed with UNION/INTERSECT/EXCEPT")));
/*
* If an internal node of a set-op tree has ORDER BY, UPDATE, or LIMIT
* clauses attached, we need to treat it like a leaf node to generate an
* independent sub-Query tree. Otherwise, it can be represented by a
* SetOperationStmt node underneath the parent Query.
*/
if (stmt->op == SETOP_NONE)
{
Assert(stmt->larg == NULL && stmt->rarg == NULL);
isLeaf = true;
}
else
{
Assert(stmt->larg != NULL && stmt->rarg != NULL);
if (stmt->sortClause || stmt->limitOffset || stmt->limitCount ||
stmt->lockingClause)
isLeaf = true;
else
isLeaf = false;
}
if (isLeaf)
{
/* Process leaf SELECT */
List *selectList;
Query *selectQuery;
char selectName[32];
RangeTblEntry *rte;
RangeTblRef *rtr;
/*
* Transform SelectStmt into a Query.
*
* Note: previously transformed sub-queries don't affect the parsing
* of this sub-query, because they are not in the toplevel pstate's
* namespace list.
*/
selectList = parse_sub_analyze((Node *) stmt, pstate);
Assert(list_length(selectList) == 1);
selectQuery = (Query *) linitial(selectList);
Assert(IsA(selectQuery, Query));
/*
* Check for bogus references to Vars on the current query level (but
* upper-level references are okay). Normally this can't happen
* because the namespace will be empty, but it could happen if we are
* inside a rule.
*/
if (pstate->p_relnamespace || pstate->p_varnamespace)
{
if (contain_vars_of_level((Node *) selectQuery, 1))
ereport(ERROR,
(errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
errmsg("UNION/INTERSECT/EXCEPT member statement may not refer to other relations of same query level")));
}
/*
* Make the leaf query be a subquery in the top-level rangetable.
*/
snprintf(selectName, sizeof(selectName), "*SELECT* %d",
list_length(pstate->p_rtable) + 1);
rte = addRangeTableEntryForSubquery(pstate,
selectQuery,
makeAlias(selectName, NIL),
false);
/*
* Return a RangeTblRef to replace the SelectStmt in the set-op tree.
*/
rtr = makeNode(RangeTblRef);
/* assume new rte is at end */
rtr->rtindex = list_length(pstate->p_rtable);
Assert(rte == rt_fetch(rtr->rtindex, pstate->p_rtable));
return (Node *) rtr;
}
else
{
/* Process an internal node (set operation node) */
SetOperationStmt *op = makeNode(SetOperationStmt);
List *lcoltypes;
List *rcoltypes;
ListCell *l;
ListCell *r;
const char *context;
context = (stmt->op == SETOP_UNION ? "UNION" :
(stmt->op == SETOP_INTERSECT ? "INTERSECT" :
"EXCEPT"));
op->op = stmt->op;
op->all = stmt->all;
/*
* Recursively transform the child nodes.
*/
op->larg = transformSetOperationTree(pstate, stmt->larg);
op->rarg = transformSetOperationTree(pstate, stmt->rarg);
/*
* Verify that the two children have the same number of non-junk
* columns, and determine the types of the merged output columns.
*/
lcoltypes = getSetColTypes(pstate, op->larg);
rcoltypes = getSetColTypes(pstate, op->rarg);
if (list_length(lcoltypes) != list_length(rcoltypes))
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("each %s query must have the same number of columns",
context)));
op->colTypes = NIL;
forboth(l, lcoltypes, r, rcoltypes)
{
Oid lcoltype = lfirst_oid(l);
Oid rcoltype = lfirst_oid(r);
Oid rescoltype;
rescoltype = select_common_type(list_make2_oid(lcoltype, rcoltype),
context);
op->colTypes = lappend_oid(op->colTypes, rescoltype);
}
return (Node *) op;
}
}
/*
* getSetColTypes
* Get output column types of an (already transformed) set-op node
*/
static List *
getSetColTypes(ParseState *pstate, Node *node)
{
if (IsA(node, RangeTblRef))
{
RangeTblRef *rtr = (RangeTblRef *) node;
RangeTblEntry *rte = rt_fetch(rtr->rtindex, pstate->p_rtable);
Query *selectQuery = rte->subquery;
List *result = NIL;
ListCell *tl;
Assert(selectQuery != NULL);
/* Get types of non-junk columns */
foreach(tl, selectQuery->targetList)
{
TargetEntry *tle = (TargetEntry *) lfirst(tl);
if (tle->resjunk)
continue;
result = lappend_oid(result, exprType((Node *) tle->expr));
}
return result;
}
else if (IsA(node, SetOperationStmt))
{
SetOperationStmt *op = (SetOperationStmt *) node;
/* Result already computed during transformation of node */
Assert(op->colTypes != NIL);
return op->colTypes;
}
else
{
elog(ERROR, "unrecognized node type: %d", (int) nodeTag(node));
return NIL; /* keep compiler quiet */
}
}
/* Attach column names from a ColumnDef list to a TargetEntry list */
static void
applyColumnNames(List *dst, List *src)
{
ListCell *dst_item;
ListCell *src_item;
if (list_length(src) > list_length(dst))
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("CREATE TABLE AS specifies too many column names")));
forboth(dst_item, dst, src_item, src)
{
TargetEntry *d = (TargetEntry *) lfirst(dst_item);
ColumnDef *s = (ColumnDef *) lfirst(src_item);
Assert(!d->resjunk);
d->resname = pstrdup(s->colname);
}
}
/*
* transformUpdateStmt -
* transforms an update statement
*/
static Query *
transformUpdateStmt(ParseState *pstate, UpdateStmt *stmt)
{
Query *qry = makeNode(Query);
Node *qual;
ListCell *origTargetList;
ListCell *tl;
qry->commandType = CMD_UPDATE;
pstate->p_is_update = true;
qry->resultRelation = setTargetTable(pstate, stmt->relation,
interpretInhOption(stmt->relation->inhOpt),
true,
ACL_UPDATE);
/*
* the FROM clause is non-standard SQL syntax. We used to be able to do
* this with REPLACE in POSTQUEL so we keep the feature.
*/
transformFromClause(pstate, stmt->fromClause);
qry->targetList = transformTargetList(pstate, stmt->targetList);
qual = transformWhereClause(pstate, stmt->whereClause, "WHERE");
qry->rtable = pstate->p_rtable;
qry->jointree = makeFromExpr(pstate->p_joinlist, qual);
qry->hasSubLinks = pstate->p_hasSubLinks;
/*
* Top-level aggregates are simply disallowed in UPDATE, per spec.
* (From an implementation point of view, this is forced because the
* implicit ctid reference would otherwise be an ungrouped variable.)
*/
if (pstate->p_hasAggs)
ereport(ERROR,
(errcode(ERRCODE_GROUPING_ERROR),
errmsg("cannot use aggregate function in UPDATE")));
/*
* Now we are done with SELECT-like processing, and can get on with
* transforming the target list to match the UPDATE target columns.
*/
/* Prepare to assign non-conflicting resnos to resjunk attributes */
if (pstate->p_next_resno <= pstate->p_target_relation->rd_rel->relnatts)
pstate->p_next_resno = pstate->p_target_relation->rd_rel->relnatts + 1;
/* Prepare non-junk columns for assignment to target table */
origTargetList = list_head(stmt->targetList);
foreach(tl, qry->targetList)
{
TargetEntry *tle = (TargetEntry *) lfirst(tl);
ResTarget *origTarget;
int attrno;
if (tle->resjunk)
{
/*
* Resjunk nodes need no additional processing, but be sure they
* have resnos that do not match any target columns; else rewriter
* or planner might get confused. They don't need a resname
* either.
*/
tle->resno = (AttrNumber) pstate->p_next_resno++;
tle->resname = NULL;
continue;
}
if (origTargetList == NULL)
elog(ERROR, "UPDATE target count mismatch --- internal error");
origTarget = (ResTarget *) lfirst(origTargetList);
Assert(IsA(origTarget, ResTarget));
attrno = attnameAttNum(pstate->p_target_relation,
origTarget->name, true);
if (attrno == InvalidAttrNumber)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_COLUMN),
errmsg("column \"%s\" of relation \"%s\" does not exist",
origTarget->name,
RelationGetRelationName(pstate->p_target_relation)),
parser_errposition(pstate, origTarget->location)));
updateTargetListEntry(pstate, tle, origTarget->name,
attrno,
origTarget->indirection,
origTarget->location);
origTargetList = lnext(origTargetList);
}
if (origTargetList != NULL)
elog(ERROR, "UPDATE target count mismatch --- internal error");
return qry;
}
/*
* tranformAlterTableStmt -
* transform an Alter Table Statement
*/
static Query *
transformAlterTableStmt(ParseState *pstate, AlterTableStmt *stmt,
List **extras_before, List **extras_after)
{
CreateStmtContext cxt;
Query *qry;
ListCell *lcmd,
*l;
List *newcmds = NIL;
bool skipValidation = true;
AlterTableCmd *newcmd;
cxt.stmtType = "ALTER TABLE";
cxt.relation = stmt->relation;
cxt.inhRelations = NIL;
cxt.isalter = true;
cxt.hasoids = false; /* need not be right */
cxt.columns = NIL;
cxt.ckconstraints = NIL;
cxt.fkconstraints = NIL;
cxt.ixconstraints = NIL;
cxt.blist = NIL;
cxt.alist = NIL;
cxt.pkey = NULL;
/*
* The only subtypes that currently require parse transformation handling
* are ADD COLUMN and ADD CONSTRAINT. These largely re-use code from
* CREATE TABLE.
*/
foreach(lcmd, stmt->cmds)
{
AlterTableCmd *cmd = (AlterTableCmd *) lfirst(lcmd);
switch (cmd->subtype)
{
case AT_AddColumn:
{
ColumnDef *def = (ColumnDef *) cmd->def;
Assert(IsA(cmd->def, ColumnDef));
transformColumnDefinition(pstate, &cxt,
(ColumnDef *) cmd->def);
/*
* If the column has a non-null default, we can't skip
* validation of foreign keys.
*/
if (((ColumnDef *) cmd->def)->raw_default != NULL)
skipValidation = false;
newcmds = lappend(newcmds, cmd);
/*
* Convert an ADD COLUMN ... NOT NULL constraint to a
* separate command
*/
if (def->is_not_null)
{
/* Remove NOT NULL from AddColumn */
def->is_not_null = false;
/* Add as a separate AlterTableCmd */
newcmd = makeNode(AlterTableCmd);
newcmd->subtype = AT_SetNotNull;
newcmd->name = pstrdup(def->colname);
newcmds = lappend(newcmds, newcmd);
}
/*
* All constraints are processed in other ways. Remove the
* original list
*/
def->constraints = NIL;
break;
}
case AT_AddConstraint:
/*
* The original AddConstraint cmd node doesn't go to newcmds
*/
if (IsA(cmd->def, Constraint))
transformTableConstraint(pstate, &cxt,
(Constraint *) cmd->def);
else if (IsA(cmd->def, FkConstraint))
{
cxt.fkconstraints = lappend(cxt.fkconstraints, cmd->def);
skipValidation = false;
}
else
elog(ERROR, "unrecognized node type: %d",
(int) nodeTag(cmd->def));
break;
case AT_ProcessedConstraint:
/*
* Already-transformed ADD CONSTRAINT, so just make it look
* like the standard case.
*/
cmd->subtype = AT_AddConstraint;
newcmds = lappend(newcmds, cmd);
break;
default:
newcmds = lappend(newcmds, cmd);
break;
}
}
/* Postprocess index and FK constraints */
transformIndexConstraints(pstate, &cxt);
transformFKConstraints(pstate, &cxt, skipValidation, true);
/*
* Push any index-creation commands into the ALTER, so that they can be
* scheduled nicely by tablecmds.c.
*/
foreach(l, cxt.alist)
{
Node *idxstmt = (Node *) lfirst(l);
Assert(IsA(idxstmt, IndexStmt));
newcmd = makeNode(AlterTableCmd);
newcmd->subtype = AT_AddIndex;
newcmd->def = idxstmt;
newcmds = lappend(newcmds, newcmd);
}
cxt.alist = NIL;
/* Append any CHECK or FK constraints to the commands list */
foreach(l, cxt.ckconstraints)
{
newcmd = makeNode(AlterTableCmd);
newcmd->subtype = AT_AddConstraint;
newcmd->def = (Node *) lfirst(l);
newcmds = lappend(newcmds, newcmd);
}
foreach(l, cxt.fkconstraints)
{
newcmd = makeNode(AlterTableCmd);
newcmd->subtype = AT_AddConstraint;
newcmd->def = (Node *) lfirst(l);
newcmds = lappend(newcmds, newcmd);
}
/* Update statement's commands list */
stmt->cmds = newcmds;
qry = makeNode(Query);
qry->commandType = CMD_UTILITY;
qry->utilityStmt = (Node *) stmt;
*extras_before = list_concat(*extras_before, cxt.blist);
*extras_after = list_concat(cxt.alist, *extras_after);
return qry;
}
static Query *
transformDeclareCursorStmt(ParseState *pstate, DeclareCursorStmt *stmt)
{
Query *result = makeNode(Query);
List *extras_before = NIL,
*extras_after = NIL;
result->commandType = CMD_UTILITY;
result->utilityStmt = (Node *) stmt;
/*
* Don't allow both SCROLL and NO SCROLL to be specified
*/
if ((stmt->options & CURSOR_OPT_SCROLL) &&
(stmt->options & CURSOR_OPT_NO_SCROLL))
ereport(ERROR,
(errcode(ERRCODE_INVALID_CURSOR_DEFINITION),
errmsg("cannot specify both SCROLL and NO SCROLL")));
stmt->query = (Node *) transformStmt(pstate, stmt->query,
&extras_before, &extras_after);
/* Shouldn't get any extras, since grammar only allows SelectStmt */
if (extras_before || extras_after)
elog(ERROR, "unexpected extra stuff in cursor statement");
return result;
}
static Query *
transformPrepareStmt(ParseState *pstate, PrepareStmt *stmt)
{
Query *result = makeNode(Query);
List *argtype_oids; /* argtype OIDs in a list */
Oid *argtoids = NULL; /* and as an array */
int nargs;
List *queries;
int i;
result->commandType = CMD_UTILITY;
result->utilityStmt = (Node *) stmt;
/* Transform list of TypeNames to list (and array) of type OIDs */
nargs = list_length(stmt->argtypes);
if (nargs)
{
ListCell *l;
argtoids = (Oid *) palloc(nargs * sizeof(Oid));
i = 0;
foreach(l, stmt->argtypes)
{
TypeName *tn = lfirst(l);
Oid toid = typenameTypeId(pstate, tn);
argtoids[i++] = toid;
}
}
/*
* Analyze the statement using these parameter types (any
* parameters passed in from above us will not be visible to it),
* allowing information about unknown parameters to be deduced
* from context.
*/
queries = parse_analyze_varparams((Node *) stmt->query,
pstate->p_sourcetext,
&argtoids, &nargs);
/*
* Shouldn't get any extra statements, since grammar only allows
* OptimizableStmt
*/
if (list_length(queries) != 1)
elog(ERROR, "unexpected extra stuff in prepared statement");
/*
* Check that all parameter types were determined, and convert the
* array of OIDs into a list for storage.
*/
argtype_oids = NIL;
for (i = 0; i < nargs; i++)
{
Oid argtype = argtoids[i];
if (argtype == InvalidOid || argtype == UNKNOWNOID)
ereport(ERROR,
(errcode(ERRCODE_INDETERMINATE_DATATYPE),
errmsg("could not determine data type of parameter $%d",
i + 1)));
argtype_oids = lappend_oid(argtype_oids, argtype);
}
stmt->argtype_oids = argtype_oids;
stmt->query = linitial(queries);
return result;
}
static Query *
transformExecuteStmt(ParseState *pstate, ExecuteStmt *stmt)
{
Query *result = makeNode(Query);
List *paramtypes;
result->commandType = CMD_UTILITY;
result->utilityStmt = (Node *) stmt;
paramtypes = FetchPreparedStatementParams(stmt->name);
stmt->into_has_oids = interpretOidsOption(stmt->into_contains_oids);
if (stmt->params || paramtypes)
{
int nparams = list_length(stmt->params);
int nexpected = list_length(paramtypes);
ListCell *l,
*l2;
int i = 1;
if (nparams != nexpected)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("wrong number of parameters for prepared statement \"%s\"",
stmt->name),
errdetail("Expected %d parameters but got %d.",
nexpected, nparams)));
forboth(l, stmt->params, l2, paramtypes)
{
Node *expr = lfirst(l);
Oid expected_type_id = lfirst_oid(l2);
Oid given_type_id;
expr = transformExpr(pstate, expr);
/* Cannot contain subselects or aggregates */
if (pstate->p_hasSubLinks)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot use subquery in EXECUTE parameter")));
if (pstate->p_hasAggs)
ereport(ERROR,
(errcode(ERRCODE_GROUPING_ERROR),
errmsg("cannot use aggregate function in EXECUTE parameter")));
given_type_id = exprType(expr);
expr = coerce_to_target_type(pstate, expr, given_type_id,
expected_type_id, -1,
COERCION_ASSIGNMENT,
COERCE_IMPLICIT_CAST);
if (expr == NULL)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("parameter $%d of type %s cannot be coerced to the expected type %s",
i,
format_type_be(given_type_id),
format_type_be(expected_type_id)),
errhint("You will need to rewrite or cast the expression.")));
lfirst(l) = expr;
i++;
}
}
return result;
}
/* exported so planner can check again after rewriting, query pullup, etc */
void
CheckSelectLocking(Query *qry)
{
if (qry->setOperations)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SELECT FOR UPDATE/SHARE is not allowed with UNION/INTERSECT/EXCEPT")));
if (qry->distinctClause != NIL)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SELECT FOR UPDATE/SHARE is not allowed with DISTINCT clause")));
if (qry->groupClause != NIL)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SELECT FOR UPDATE/SHARE is not allowed with GROUP BY clause")));
if (qry->havingQual != NULL)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SELECT FOR UPDATE/SHARE is not allowed with HAVING clause")));
if (qry->hasAggs)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SELECT FOR UPDATE/SHARE is not allowed with aggregate functions")));
}
/*
* Transform a FOR UPDATE/SHARE clause
*
* This basically involves replacing names by integer relids.
*
* NB: if you need to change this, see also markQueryForLocking()
* in rewriteHandler.c.
*/
static void
transformLockingClause(Query *qry, LockingClause *lc)
{
List *lockedRels = lc->lockedRels;
ListCell *l;
ListCell *rt;
Index i;
LockingClause *allrels;
CheckSelectLocking(qry);
/* make a clause we can pass down to subqueries to select all rels */
allrels = makeNode(LockingClause);
allrels->lockedRels = NIL; /* indicates all rels */
allrels->forUpdate = lc->forUpdate;
allrels->noWait = lc->noWait;
if (lockedRels == NIL)
{
/* all regular tables used in query */
i = 0;
foreach(rt, qry->rtable)
{
RangeTblEntry *rte = (RangeTblEntry *) lfirst(rt);
++i;
switch (rte->rtekind)
{
case RTE_RELATION:
applyLockingClause(qry, i, lc->forUpdate, lc->noWait);
rte->requiredPerms |= ACL_SELECT_FOR_UPDATE;
break;
case RTE_SUBQUERY:
/*
* FOR UPDATE/SHARE of subquery is propagated to all of
* subquery's rels
*/
transformLockingClause(rte->subquery, allrels);
break;
default:
/* ignore JOIN, SPECIAL, FUNCTION RTEs */
break;
}
}
}
else
{
/* just the named tables */
foreach(l, lockedRels)
{
char *relname = strVal(lfirst(l));
i = 0;
foreach(rt, qry->rtable)
{
RangeTblEntry *rte = (RangeTblEntry *) lfirst(rt);
++i;
if (strcmp(rte->eref->aliasname, relname) == 0)
{
switch (rte->rtekind)
{
case RTE_RELATION:
applyLockingClause(qry, i,
lc->forUpdate, lc->noWait);
rte->requiredPerms |= ACL_SELECT_FOR_UPDATE;
break;
case RTE_SUBQUERY:
/*
* FOR UPDATE/SHARE of subquery is propagated to
* all of subquery's rels
*/
transformLockingClause(rte->subquery, allrels);
break;
case RTE_JOIN:
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SELECT FOR UPDATE/SHARE cannot be applied to a join")));
break;
case RTE_SPECIAL:
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SELECT FOR UPDATE/SHARE cannot be applied to NEW or OLD")));
break;
case RTE_FUNCTION:
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SELECT FOR UPDATE/SHARE cannot be applied to a function")));
break;
default:
elog(ERROR, "unrecognized RTE type: %d",
(int) rte->rtekind);
break;
}
break; /* out of foreach loop */
}
}
if (rt == NULL)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_TABLE),
errmsg("relation \"%s\" in FOR UPDATE/SHARE clause not found in FROM clause",
relname)));
}
}
}
/*
* Record locking info for a single rangetable item
*/
void
applyLockingClause(Query *qry, Index rtindex, bool forUpdate, bool noWait)
{
RowMarkClause *rc;
/* Check for pre-existing entry for same rtindex */
if ((rc = get_rowmark(qry, rtindex)) != NULL)
{
/*
* If the same RTE is specified both FOR UPDATE and FOR SHARE,
* treat it as FOR UPDATE. (Reasonable, since you can't take
* both a shared and exclusive lock at the same time; it'll
* end up being exclusive anyway.)
*
* We also consider that NOWAIT wins if it's specified both ways.
* This is a bit more debatable but raising an error doesn't
* seem helpful. (Consider for instance SELECT FOR UPDATE NOWAIT
* from a view that internally contains a plain FOR UPDATE spec.)
*/
rc->forUpdate |= forUpdate;
rc->noWait |= noWait;
return;
}
/* Make a new RowMarkClause */
rc = makeNode(RowMarkClause);
rc->rti = rtindex;
rc->forUpdate = forUpdate;
rc->noWait = noWait;
qry->rowMarks = lappend(qry->rowMarks, rc);
}
/*
* Preprocess a list of column constraint clauses
* to attach constraint attributes to their primary constraint nodes
* and detect inconsistent/misplaced constraint attributes.
*
* NOTE: currently, attributes are only supported for FOREIGN KEY primary
* constraints, but someday they ought to be supported for other constraints.
*/
static void
transformConstraintAttrs(List *constraintList)
{
Node *lastprimarynode = NULL;
bool saw_deferrability = false;
bool saw_initially = false;
ListCell *clist;
foreach(clist, constraintList)
{
Node *node = lfirst(clist);
if (!IsA(node, Constraint))
{
lastprimarynode = node;
/* reset flags for new primary node */
saw_deferrability = false;
saw_initially = false;
}
else
{
Constraint *con = (Constraint *) node;
switch (con->contype)
{
case CONSTR_ATTR_DEFERRABLE:
if (lastprimarynode == NULL ||
!IsA(lastprimarynode, FkConstraint))
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("misplaced DEFERRABLE clause")));
if (saw_deferrability)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("multiple DEFERRABLE/NOT DEFERRABLE clauses not allowed")));
saw_deferrability = true;
((FkConstraint *) lastprimarynode)->deferrable = true;
break;
case CONSTR_ATTR_NOT_DEFERRABLE:
if (lastprimarynode == NULL ||
!IsA(lastprimarynode, FkConstraint))
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("misplaced NOT DEFERRABLE clause")));
if (saw_deferrability)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("multiple DEFERRABLE/NOT DEFERRABLE clauses not allowed")));
saw_deferrability = true;
((FkConstraint *) lastprimarynode)->deferrable = false;
if (saw_initially &&
((FkConstraint *) lastprimarynode)->initdeferred)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("constraint declared INITIALLY DEFERRED must be DEFERRABLE")));
break;
case CONSTR_ATTR_DEFERRED:
if (lastprimarynode == NULL ||
!IsA(lastprimarynode, FkConstraint))
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("misplaced INITIALLY DEFERRED clause")));
if (saw_initially)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("multiple INITIALLY IMMEDIATE/DEFERRED clauses not allowed")));
saw_initially = true;
((FkConstraint *) lastprimarynode)->initdeferred = true;
/*
* If only INITIALLY DEFERRED appears, assume DEFERRABLE
*/
if (!saw_deferrability)
((FkConstraint *) lastprimarynode)->deferrable = true;
else if (!((FkConstraint *) lastprimarynode)->deferrable)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("constraint declared INITIALLY DEFERRED must be DEFERRABLE")));
break;
case CONSTR_ATTR_IMMEDIATE:
if (lastprimarynode == NULL ||
!IsA(lastprimarynode, FkConstraint))
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("misplaced INITIALLY IMMEDIATE clause")));
if (saw_initially)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("multiple INITIALLY IMMEDIATE/DEFERRED clauses not allowed")));
saw_initially = true;
((FkConstraint *) lastprimarynode)->initdeferred = false;
break;
default:
/* Otherwise it's not an attribute */
lastprimarynode = node;
/* reset flags for new primary node */
saw_deferrability = false;
saw_initially = false;
break;
}
}
}
}
/* Build a FromExpr node */
static FromExpr *
makeFromExpr(List *fromlist, Node *quals)
{
FromExpr *f = makeNode(FromExpr);
f->fromlist = fromlist;
f->quals = quals;
return f;
}
/*
* Special handling of type definition for a column
*/
static void
transformColumnType(ParseState *pstate, ColumnDef *column)
{
/*
* All we really need to do here is verify that the type is valid.
*/
Type ctype = typenameType(pstate, column->typename);
ReleaseSysCache(ctype);
}
static void
setSchemaName(char *context_schema, char **stmt_schema_name)
{
if (*stmt_schema_name == NULL)
*stmt_schema_name = context_schema;
else if (strcmp(context_schema, *stmt_schema_name) != 0)
ereport(ERROR,
(errcode(ERRCODE_INVALID_SCHEMA_DEFINITION),
errmsg("CREATE specifies a schema (%s) "
"different from the one being created (%s)",
*stmt_schema_name, context_schema)));
}
/*
* analyzeCreateSchemaStmt -
* analyzes the "create schema" statement
*
* Split the schema element list into individual commands and place
* them in the result list in an order such that there are no forward
* references (e.g. GRANT to a table created later in the list). Note
* that the logic we use for determining forward references is
* presently quite incomplete.
*
* SQL92 also allows constraints to make forward references, so thumb through
* the table columns and move forward references to a posterior alter-table
* command.
*
* The result is a list of parse nodes that still need to be analyzed ---
* but we can't analyze the later commands until we've executed the earlier
* ones, because of possible inter-object references.
*
* Note: Called from commands/schemacmds.c
*/
List *
analyzeCreateSchemaStmt(CreateSchemaStmt *stmt)
{
CreateSchemaStmtContext cxt;
List *result;
ListCell *elements;
cxt.stmtType = "CREATE SCHEMA";
cxt.schemaname = stmt->schemaname;
cxt.authid = stmt->authid;
cxt.sequences = NIL;
cxt.tables = NIL;
cxt.views = NIL;
cxt.indexes = NIL;
cxt.grants = NIL;
cxt.triggers = NIL;
cxt.fwconstraints = NIL;
cxt.alters = NIL;
cxt.blist = NIL;
cxt.alist = NIL;
/*
* Run through each schema element in the schema element list. Separate
* statements by type, and do preliminary analysis.
*/
foreach(elements, stmt->schemaElts)
{
Node *element = lfirst(elements);
switch (nodeTag(element))
{
case T_CreateSeqStmt:
{
CreateSeqStmt *elp = (CreateSeqStmt *) element;
setSchemaName(cxt.schemaname, &elp->sequence->schemaname);
cxt.sequences = lappend(cxt.sequences, element);
}
break;
case T_CreateStmt:
{
CreateStmt *elp = (CreateStmt *) element;
setSchemaName(cxt.schemaname, &elp->relation->schemaname);
/*
* XXX todo: deal with constraints
*/
cxt.tables = lappend(cxt.tables, element);
}
break;
case T_ViewStmt:
{
ViewStmt *elp = (ViewStmt *) element;
setSchemaName(cxt.schemaname, &elp->view->schemaname);
/*
* XXX todo: deal with references between views
*/
cxt.views = lappend(cxt.views, element);
}
break;
case T_IndexStmt:
{
IndexStmt *elp = (IndexStmt *) element;
setSchemaName(cxt.schemaname, &elp->relation->schemaname);
cxt.indexes = lappend(cxt.indexes, element);
}
break;
case T_CreateTrigStmt:
{
CreateTrigStmt *elp = (CreateTrigStmt *) element;
setSchemaName(cxt.schemaname, &elp->relation->schemaname);
cxt.triggers = lappend(cxt.triggers, element);
}
break;
case T_GrantStmt:
cxt.grants = lappend(cxt.grants, element);
break;
default:
elog(ERROR, "unrecognized node type: %d",
(int) nodeTag(element));
}
}
result = NIL;
result = list_concat(result, cxt.sequences);
result = list_concat(result, cxt.tables);
result = list_concat(result, cxt.views);
result = list_concat(result, cxt.indexes);
result = list_concat(result, cxt.triggers);
result = list_concat(result, cxt.grants);
return result;
}
/*
* Traverse a fully-analyzed tree to verify that parameter symbols
* match their types. We need this because some Params might still
* be UNKNOWN, if there wasn't anything to force their coercion,
* and yet other instances seen later might have gotten coerced.
*/
static bool
check_parameter_resolution_walker(Node *node,
check_parameter_resolution_context *context)
{
if (node == NULL)
return false;
if (IsA(node, Param))
{
Param *param = (Param *) node;
if (param->paramkind == PARAM_EXTERN)
{
int paramno = param->paramid;
if (paramno <= 0 || /* shouldn't happen, but... */
paramno > context->numParams)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_PARAMETER),
errmsg("there is no parameter $%d", paramno)));
if (param->paramtype != context->paramTypes[paramno - 1])
ereport(ERROR,
(errcode(ERRCODE_AMBIGUOUS_PARAMETER),
errmsg("could not determine data type of parameter $%d",
paramno)));
}
return false;
}
if (IsA(node, Query))
{
/* Recurse into RTE subquery or not-yet-planned sublink subquery */
return query_tree_walker((Query *) node,
check_parameter_resolution_walker,
(void *) context, 0);
}
return expression_tree_walker(node, check_parameter_resolution_walker,
(void *) context);
}
View Git Blame Copy Permalink