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Extend pg_cast castimplicit column to a three-way value; this allows us

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to be flexible about assignment casts without introducing ambiguity in
operator/function resolution.  Introduce a well-defined promotion hierarchy
for numeric datatypes (int2->int4->int8->numeric->float4->float8).
Change make_const to initially label numeric literals as int4, int8, or
numeric (never float8 anymore).
Explicitly mark Func and RelabelType nodes to indicate whether they came
from a function call, explicit cast, or implicit cast; use this to do
reverse-listing more accurately and without so many heuristics.
Explicit casts to char, varchar, bit, varbit will truncate or pad without
raising an error (the pre-7.2 behavior), while assigning to a column without
any explicit cast will still raise an error for wrong-length data like 7.3.
This more nearly follows the SQL spec than 7.2 behavior (we should be
reporting a 'completion condition' in the explicit-cast cases, but we have
no mechanism for that, so just do silent truncation).
Fix some problems with enforcement of typmod for array elements;
it didn't work at all in 'UPDATE ... SET array[n] = foo', for example.
Provide a generalized array_length_coerce() function to replace the
specialized per-array-type functions that used to be needed (and were
missing for NUMERIC as well as all the datetime types).
Add missing conversions int8<->float4, text<->numeric, oid<->int8.
initdb forced.
This commit is contained in:
Tom Lane
2002-09-18 21:35:25 +00:00
parent cc70ba2e4d
commit b26dfb9522
70 changed files with 1642 additions and 1528 deletions
Download Patch File Download Diff File Expand all files Collapse all files

413
src/backend/parser/parse_coerce.c
View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/parser/parse_coerce.c,v 2.83 2002/09/04 20:31:23 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/parser/parse_coerce.c,v 2.84 2002/09/18 21:35:22 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -23,28 +23,104 @@
#include "parser/parse_func.h"
#include "parser/parse_type.h"
#include "utils/builtins.h"
#include "utils/fmgroids.h"
#include "utils/lsyscache.h"
#include "utils/syscache.h"
static Node *coerce_type_typmod(Node *node,
Oid targetTypeId, int32 targetTypMod,
CoercionForm cformat);
static Oid PreferredType(CATEGORY category, Oid type);
static bool find_coercion_pathway(Oid targetTypeId, Oid sourceTypeId,
bool isExplicit,
Oid *funcid);
static Oid find_typmod_coercion_function(Oid typeId);
static Node *build_func_call(Oid funcid, Oid rettype, List *args);
CoercionContext ccontext,
Oid *funcid);
static Node *build_func_call(Oid funcid, Oid rettype, List *args,
CoercionForm fformat);
/*
* coerce_to_target_type()
* Convert an expression to a target type and typmod.
*
* This is the general-purpose entry point for arbitrary type coercion
* operations. Direct use of the component operations can_coerce_type,
* coerce_type, and coerce_type_typmod should be restricted to special
* cases (eg, when the conversion is expected to succeed).
*
* Returns the possibly-transformed expression tree, or NULL if the type
* conversion is not possible. (We do this, rather than elog'ing directly,
* so that callers can generate custom error messages indicating context.)
*
* expr - input expression tree (already transformed by transformExpr)
* exprtype - result type of expr
* targettype - desired result type
* targettypmod - desired result typmod
* ccontext, cformat - context indicators to control coercions
*/
Node *
coerce_to_target_type(Node *expr, Oid exprtype,
Oid targettype, int32 targettypmod,
CoercionContext ccontext,
CoercionForm cformat)
{
if (can_coerce_type(1, &exprtype, &targettype, ccontext))
expr = coerce_type(expr, exprtype, targettype,
ccontext, cformat);
/*
* String hacks to get transparent conversions for char and varchar:
* if a coercion to text is available, use it for forced coercions to
* char(n) or varchar(n).
*
* This is pretty grotty, but seems easier to maintain than providing
* entries in pg_cast that parallel all the ones for text.
*/
else if (ccontext >= COERCION_ASSIGNMENT &&
(targettype == BPCHAROID || targettype == VARCHAROID))
{
Oid text_id = TEXTOID;
if (can_coerce_type(1, &exprtype, &text_id, ccontext))
{
expr = coerce_type(expr, exprtype, text_id,
ccontext, cformat);
/* Need a RelabelType if no typmod coercion is performed */
if (targettypmod < 0)
expr = (Node *) makeRelabelType(expr, targettype, -1,
cformat);
}
else
expr = NULL;
}
else
expr = NULL;
/*
* If the target is a fixed-length type, it may need a length coercion
* as well as a type coercion.
*/
if (expr != NULL)
expr = coerce_type_typmod(expr, targettype, targettypmod, cformat);
return expr;
}
/*
* coerce_type()
* Convert a function argument to a different type.
* Convert an expression to a different type.
*
* The caller should already have determined that the coercion is possible;
* see can_coerce_type.
*
* No coercion to a typmod (length) is performed here. The caller must
* call coerce_type_typmod as well, if a typmod constraint is wanted.
* (But if the target type is a domain, it may internally contain a
* typmod constraint, which will be applied inside coerce_type_constraints.)
*/
Node *
coerce_type(ParseState *pstate, Node *node, Oid inputTypeId,
Oid targetTypeId, int32 atttypmod, bool isExplicit)
coerce_type(Node *node, Oid inputTypeId, Oid targetTypeId,
CoercionContext ccontext, CoercionForm cformat)
{
Node *result;
Oid funcId;
@ -68,7 +144,7 @@ coerce_type(ParseState *pstate, Node *node, Oid inputTypeId,
* example, int4's typinput function will reject "1.2", whereas
* float-to-int type conversion will round to integer.
*
* XXX if the typinput function is not cachable, we really ought to
* XXX if the typinput function is not immutable, we really ought to
* postpone evaluation of the function call until runtime. But
* there is no way to represent a typinput function call as an
* expression tree, because C-string values are not Datums. (XXX
@ -91,28 +167,31 @@ coerce_type(ParseState *pstate, Node *node, Oid inputTypeId,
con->constvalue));
/*
* If target is a domain, use the typmod it applies to the
* base type. Note that we call stringTypeDatum using the
* domain's pg_type row, though. This works because the
* domain row has the same typinput and typelem as the base
* type --- ugly...
* We pass typmod -1 to the input routine, primarily because
* existing input routines follow implicit-coercion semantics
* for length checks, which is not always what we want here.
* Any length constraint will be applied later by our caller.
*
* Note that we call stringTypeDatum using the domain's pg_type
* row, if it's a domain. This works because the domain row has
* the same typinput and typelem as the base type --- ugly...
*/
if (targetTyptype == 'd')
atttypmod = getBaseTypeMod(targetTypeId, atttypmod);
newcon->constvalue = stringTypeDatum(targetType, val, atttypmod);
newcon->constvalue = stringTypeDatum(targetType, val, -1);
pfree(val);
}
result = (Node *) newcon;
/*
* If target is a domain, apply constraints (except for typmod,
* which we assume the input routine took care of).
*/
/* If target is a domain, apply constraints. */
if (targetTyptype == 'd')
result = coerce_type_constraints(pstate, result, targetTypeId,
false);
{
result = coerce_type_constraints(result, targetTypeId,
cformat);
/* We might now need a RelabelType. */
if (exprType(result) != targetTypeId)
result = (Node *) makeRelabelType(result, targetTypeId, -1,
cformat);
}
ReleaseSysCache(targetType);
}
@ -120,9 +199,10 @@ coerce_type(ParseState *pstate, Node *node, Oid inputTypeId,
targetTypeId == ANYARRAYOID)
{
/* assume can_coerce_type verified that implicit coercion is okay */
/* NB: we do NOT want a RelabelType here */
result = node;
}
else if (find_coercion_pathway(targetTypeId, inputTypeId, isExplicit,
else if (find_coercion_pathway(targetTypeId, inputTypeId, ccontext,
&funcId))
{
if (OidIsValid(funcId))
@ -135,7 +215,8 @@ coerce_type(ParseState *pstate, Node *node, Oid inputTypeId,
*/
Oid baseTypeId = getBaseType(targetTypeId);
result = build_func_call(funcId, baseTypeId, makeList1(node));
result = build_func_call(funcId, baseTypeId, makeList1(node),
cformat);
/*
* If domain, test against domain constraints and relabel with
@ -143,9 +224,10 @@ coerce_type(ParseState *pstate, Node *node, Oid inputTypeId,
*/
if (targetTypeId != baseTypeId)
{
result = coerce_type_constraints(pstate, result,
targetTypeId, true);
result = (Node *) makeRelabelType(result, targetTypeId, -1);
result = coerce_type_constraints(result, targetTypeId,
cformat);
result = (Node *) makeRelabelType(result, targetTypeId, -1,
cformat);
}
/*
@ -179,8 +261,8 @@ coerce_type(ParseState *pstate, Node *node, Oid inputTypeId,
* Also, domains may have value restrictions beyond the base type
* that must be accounted for.
*/
result = coerce_type_constraints(pstate, node,
targetTypeId, true);
result = coerce_type_constraints(node, targetTypeId,
cformat);
/*
* XXX could we label result with exprTypmod(node) instead of
@ -189,7 +271,8 @@ coerce_type(ParseState *pstate, Node *node, Oid inputTypeId,
* typmod, which is likely but not certain (wrong if target is
* a domain, in any case).
*/
result = (Node *) makeRelabelType(result, targetTypeId, -1);
result = (Node *) makeRelabelType(result, targetTypeId, -1,
cformat);
}
}
else if (typeInheritsFrom(inputTypeId, targetTypeId))
@ -199,7 +282,8 @@ coerce_type(ParseState *pstate, Node *node, Oid inputTypeId,
* except relabel the type. This is binary compatibility for
* complex types.
*/
result = (Node *) makeRelabelType(node, targetTypeId, -1);
result = (Node *) makeRelabelType(node, targetTypeId, -1,
cformat);
}
else
{
@ -215,15 +299,14 @@ coerce_type(ParseState *pstate, Node *node, Oid inputTypeId,
/*
* can_coerce_type()
* Can input_typeids be coerced to func_typeids?
* Can input_typeids be coerced to target_typeids?
*
* We must be told whether this is an implicit or explicit coercion
* (explicit being a CAST construct, explicit function call, etc).
* We will accept a wider set of coercion cases for an explicit coercion.
* We must be told the context (CAST construct, assignment, implicit coercion)
* as this determines the set of available casts.
*/
bool
can_coerce_type(int nargs, Oid *input_typeids, Oid *func_typeids,
bool isExplicit)
can_coerce_type(int nargs, Oid *input_typeids, Oid *target_typeids,
CoercionContext ccontext)
{
int i;
@ -231,7 +314,7 @@ can_coerce_type(int nargs, Oid *input_typeids, Oid *func_typeids,
for (i = 0; i < nargs; i++)
{
Oid inputTypeId = input_typeids[i];
Oid targetTypeId = func_typeids[i];
Oid targetTypeId = target_typeids[i];
Oid funcId;
/* no problem if same type */
@ -278,7 +361,7 @@ can_coerce_type(int nargs, Oid *input_typeids, Oid *func_typeids,
/*
* Otherwise reject; this assumes there are no explicit
* coercions to ANYARRAY. If we don't reject then
* coercion paths to ANYARRAY. If we don't reject then
* parse_coerce would have to repeat the above test.
*/
return false;
@ -288,7 +371,7 @@ can_coerce_type(int nargs, Oid *input_typeids, Oid *func_typeids,
* If pg_cast shows that we can coerce, accept. This test now
* covers both binary-compatible and coercion-function cases.
*/
if (find_coercion_pathway(targetTypeId, inputTypeId, isExplicit,
if (find_coercion_pathway(targetTypeId, inputTypeId, ccontext,
&funcId))
continue;
@ -312,10 +395,12 @@ can_coerce_type(int nargs, Oid *input_typeids, Oid *func_typeids,
* Create an expression tree to enforce the constraints (if any)
* that should be applied by the type. Currently this is only
* interesting for domain types.
*
* NOTE: result tree is not guaranteed to show the correct exprType() for
* the domain; it may show the base type. Caller must relabel if needed.
*/
Node *
coerce_type_constraints(ParseState *pstate, Node *arg,
Oid typeId, bool applyTypmod)
coerce_type_constraints(Node *arg, Oid typeId, CoercionForm cformat)
{
char *notNull = NULL;
int32 typmod = -1;
@ -356,8 +441,8 @@ coerce_type_constraints(ParseState *pstate, Node *arg,
/*
* If domain applies a typmod to its base type, do length coercion.
*/
if (applyTypmod && typmod >= 0)
arg = coerce_type_typmod(pstate, arg, typeId, typmod);
if (typmod >= 0)
arg = coerce_type_typmod(arg, typeId, typmod, cformat);
/*
* Only need to add one NOT NULL check regardless of how many domains
@ -380,8 +465,9 @@ coerce_type_constraints(ParseState *pstate, Node *arg,
}
/* coerce_type_typmod()
* Force a value to a particular typmod, if meaningful and possible.
/*
* coerce_type_typmod()
* Force a value to a particular typmod, if meaningful and possible.
*
* This is applied to values that are going to be stored in a relation
* (where we have an atttypmod for the column) as well as values being
@ -394,33 +480,65 @@ coerce_type_constraints(ParseState *pstate, Node *arg,
* coercion for a domain is considered to be part of the type coercion
* needed to produce the domain value in the first place. So, no getBaseType.
*/
Node *
coerce_type_typmod(ParseState *pstate, Node *node,
Oid targetTypeId, int32 atttypmod)
static Node *
coerce_type_typmod(Node *node, Oid targetTypeId, int32 targetTypMod,
CoercionForm cformat)
{
Oid funcId;
int nargs;
/*
* A negative typmod is assumed to mean that no coercion is wanted.
*/
if (atttypmod < 0 || atttypmod == exprTypmod(node))
if (targetTypMod < 0 || targetTypMod == exprTypmod(node))
return node;
funcId = find_typmod_coercion_function(targetTypeId);
funcId = find_typmod_coercion_function(targetTypeId, &nargs);
if (OidIsValid(funcId))
{
List *args;
Const *cons;
Node *fcall;
/* Pass given value, plus target typmod as an int4 constant */
cons = makeConst(INT4OID,
sizeof(int32),
Int32GetDatum(atttypmod),
Int32GetDatum(targetTypMod),
false,
true,
false,
false);
node = build_func_call(funcId, targetTypeId, makeList2(node, cons));
args = makeList2(node, cons);
if (nargs == 3)
{
/* Pass it a boolean isExplicit parameter, too */
cons = makeConst(BOOLOID,
sizeof(bool),
BoolGetDatum(cformat != COERCE_IMPLICIT_CAST),
false,
true,
false,
false);
args = lappend(args, cons);
}
fcall = build_func_call(funcId, targetTypeId, args, cformat);
/*
* If the input is a constant, apply the length coercion
* function now instead of delaying to runtime.
*
* See the comments for the similar case in coerce_type.
*/
if (node && IsA(node, Const) &&
!((Const *) node)->constisnull)
node = eval_const_expressions(fcall);
else
node = fcall;
}
return node;
@ -437,19 +555,19 @@ Node *
coerce_to_boolean(Node *node, const char *constructName)
{
Oid inputTypeId = exprType(node);
Oid targetTypeId;
if (inputTypeId != BOOLOID)
{
targetTypeId = BOOLOID;
if (!can_coerce_type(1, &inputTypeId, &targetTypeId, false))
node = coerce_to_target_type(node, inputTypeId,
BOOLOID, -1,
COERCION_ASSIGNMENT,
COERCE_IMPLICIT_CAST);
if (node == NULL)
{
/* translator: first %s is name of a SQL construct, eg WHERE */
elog(ERROR, "Argument of %s must be type boolean, not type %s",
constructName, format_type_be(inputTypeId));
}
node = coerce_type(NULL, node, inputTypeId, targetTypeId, -1,
false);
}
if (expression_returns_set(node))
@ -472,12 +590,6 @@ coerce_to_boolean(Node *node, const char *constructName)
* in the list will be preferred if there is doubt.
* 'context' is a phrase to use in the error message if we fail to select
* a usable type.
*
* XXX this code is WRONG, since (for example) given the input (int4,int8)
* it will select int4, whereas according to SQL92 clause 9.3 the correct
* answer is clearly int8. To fix this we need a notion of a promotion
* hierarchy within type categories --- something more complete than
* just a single preferred type.
*/
Oid
select_common_type(List *typeids, const char *context)
@ -511,12 +623,13 @@ select_common_type(List *typeids, const char *context)
elog(ERROR, "%s types '%s' and '%s' not matched",
context, format_type_be(ptype), format_type_be(ntype));
}
else if (IsPreferredType(pcategory, ntype)
&& !IsPreferredType(pcategory, ptype)
&& can_coerce_type(1, &ptype, &ntype, false))
else if (!IsPreferredType(pcategory, ptype) &&
can_coerce_type(1, &ptype, &ntype, COERCION_IMPLICIT) &&
!can_coerce_type(1, &ntype, &ptype, COERCION_IMPLICIT))
{
/*
* new one is preferred and can convert? then take it...
* take new type if can coerce to it implicitly but not the
* other way; but if we have a preferred type, stay on it.
*/
ptype = ntype;
pcategory = TypeCategory(ptype);
@ -547,26 +660,20 @@ select_common_type(List *typeids, const char *context)
* This is used following select_common_type() to coerce the individual
* expressions to the desired type. 'context' is a phrase to use in the
* error message if we fail to coerce.
*
* NOTE: pstate may be NULL.
*/
Node *
coerce_to_common_type(ParseState *pstate, Node *node,
Oid targetTypeId,
const char *context)
coerce_to_common_type(Node *node, Oid targetTypeId, const char *context)
{
Oid inputTypeId = exprType(node);
if (inputTypeId == targetTypeId)
return node; /* no work */
if (can_coerce_type(1, &inputTypeId, &targetTypeId, false))
node = coerce_type(pstate, node, inputTypeId, targetTypeId, -1,
false);
if (can_coerce_type(1, &inputTypeId, &targetTypeId, COERCION_IMPLICIT))
node = coerce_type(node, inputTypeId, targetTypeId,
COERCION_IMPLICIT, COERCE_IMPLICIT_CAST);
else
{
elog(ERROR, "%s unable to convert to type %s",
context, format_type_be(targetTypeId));
}
return node;
}
@ -708,8 +815,6 @@ PreferredType(CATEGORY category, Oid type)
type == REGCLASSOID ||
type == REGTYPEOID)
result = OIDOID;
else if (type == NUMERICOID)
result = NUMERICOID;
else
result = FLOAT8OID;
break;
@ -742,49 +847,52 @@ PreferredType(CATEGORY category, Oid type)
} /* PreferredType() */
/* IsBinaryCompatible()
* Check if two types are binary-compatible.
/* IsBinaryCoercible()
* Check if srctype is binary-coercible to targettype.
*
* This notion allows us to cheat and directly exchange values without
* going through the trouble of calling a conversion function.
*
* As of 7.3, binary compatibility isn't hardwired into the code anymore.
* We consider two types binary-compatible if there is an implicit,
* no-function-needed pg_cast entry. NOTE that we assume that such
* entries are symmetric, ie, it doesn't matter which type we consider
* source and which target. (cf. checks in opr_sanity regression test)
* As of 7.3, binary coercibility isn't hardwired into the code anymore.
* We consider two types binary-coercible if there is an implicitly
* invokable, no-function-needed pg_cast entry.
*
* This function replaces IsBinaryCompatible(), which was an inherently
* symmetric test. Since the pg_cast entries aren't necessarily symmetric,
* the order of the operands is now significant.
*/
bool
IsBinaryCompatible(Oid type1, Oid type2)
IsBinaryCoercible(Oid srctype, Oid targettype)
{
HeapTuple tuple;
Form_pg_cast castForm;
bool result;
/* Fast path if same type */
if (type1 == type2)
if (srctype == targettype)
return true;
/* Perhaps the types are domains; if so, look at their base types */
if (OidIsValid(type1))
type1 = getBaseType(type1);
if (OidIsValid(type2))
type2 = getBaseType(type2);
if (OidIsValid(srctype))
srctype = getBaseType(srctype);
if (OidIsValid(targettype))
targettype = getBaseType(targettype);
/* Somewhat-fast path if same base type */
if (type1 == type2)
if (srctype == targettype)
return true;
/* Else look in pg_cast */
tuple = SearchSysCache(CASTSOURCETARGET,
ObjectIdGetDatum(type1),
ObjectIdGetDatum(type2),
ObjectIdGetDatum(srctype),
ObjectIdGetDatum(targettype),
0, 0);
if (!HeapTupleIsValid(tuple))
return false; /* no cast */
castForm = (Form_pg_cast) GETSTRUCT(tuple);
result = (castForm->castfunc == InvalidOid) && castForm->castimplicit;
result = (castForm->castfunc == InvalidOid &&
castForm->castcontext == COERCION_CODE_IMPLICIT);
ReleaseSysCache(tuple);
@ -796,12 +904,15 @@ IsBinaryCompatible(Oid type1, Oid type2)
* find_coercion_pathway
* Look for a coercion pathway between two types.
*
* If we find a matching entry in pg_cast, return TRUE, and set *funcid
* ccontext determines the set of available casts.
*
* If we find a suitable entry in pg_cast, return TRUE, and set *funcid
* to the castfunc value (which may be InvalidOid for a binary-compatible
* coercion).
*/
static bool
find_coercion_pathway(Oid targetTypeId, Oid sourceTypeId, bool isExplicit,
find_coercion_pathway(Oid targetTypeId, Oid sourceTypeId,
CoercionContext ccontext,
Oid *funcid)
{
bool result = false;
@ -828,8 +939,29 @@ find_coercion_pathway(Oid targetTypeId, Oid sourceTypeId, bool isExplicit,
if (HeapTupleIsValid(tuple))
{
Form_pg_cast castForm = (Form_pg_cast) GETSTRUCT(tuple);
CoercionContext castcontext;
if (isExplicit || castForm->castimplicit)
/* convert char value for castcontext to CoercionContext enum */
switch (castForm->castcontext)
{
case COERCION_CODE_IMPLICIT:
castcontext = COERCION_IMPLICIT;
break;
case COERCION_CODE_ASSIGNMENT:
castcontext = COERCION_ASSIGNMENT;
break;
case COERCION_CODE_EXPLICIT:
castcontext = COERCION_EXPLICIT;
break;
default:
elog(ERROR, "find_coercion_pathway: bogus castcontext %c",
castForm->castcontext);
castcontext = 0; /* keep compiler quiet */
break;
}
/* Rely on ordering of enum for correct behavior here */
if (ccontext >= castcontext)
{
*funcid = castForm->castfunc;
result = true;
@ -850,30 +982,59 @@ find_coercion_pathway(Oid targetTypeId, Oid sourceTypeId, bool isExplicit,
* the type requires coercion to its own length and that the said
* function should be invoked to do that.
*
* Alternatively, the length-coercing function may have the signature
* (targettype, int4, bool). On success, *nargs is set to report which
* signature we found.
*
* "bpchar" (ie, char(N)) and "numeric" are examples of such types.
*
* If the given type is a varlena array type, we do not look for a coercion
* function associated directly with the array type, but instead look for
* one associated with the element type. If one exists, we report
* array_length_coerce() as the coercion function to use.
*
* This mechanism may seem pretty grotty and in need of replacement by
* something in pg_cast, but since typmod is only interesting for datatypes
* that have special handling in the grammar, there's not really much
* percentage in making it any easier to apply such coercions ...
*/
static Oid
find_typmod_coercion_function(Oid typeId)
Oid
find_typmod_coercion_function(Oid typeId, int *nargs)
{
Oid funcid = InvalidOid;
bool isArray = false;
Type targetType;
Form_pg_type typeForm;
char *typname;
Oid typnamespace;
Oid oid_array[FUNC_MAX_ARGS];
HeapTuple ftup;
targetType = typeidType(typeId);
typname = NameStr(((Form_pg_type) GETSTRUCT(targetType))->typname);
typnamespace = ((Form_pg_type) GETSTRUCT(targetType))->typnamespace;
typeForm = (Form_pg_type) GETSTRUCT(targetType);
/* Check for a varlena array type (and not a domain) */
if (typeForm->typelem != InvalidOid &&
typeForm->typlen == -1 &&
typeForm->typtype != 'd')
{
/* Yes, switch our attention to the element type */
typeId = typeForm->typelem;
ReleaseSysCache(targetType);
targetType = typeidType(typeId);
typeForm = (Form_pg_type) GETSTRUCT(targetType);
isArray = true;
}
/* Function name is same as type internal name, and in same namespace */
typname = NameStr(typeForm->typname);
typnamespace = typeForm->typnamespace;
/* First look for parameters (type, int4) */
MemSet(oid_array, 0, FUNC_MAX_ARGS * sizeof(Oid));
oid_array[0] = typeId;
oid_array[1] = INT4OID;
*nargs = 2;
ftup = SearchSysCache(PROCNAMENSP,
CStringGetDatum(typname),
@ -894,8 +1055,45 @@ find_typmod_coercion_function(Oid typeId)
ReleaseSysCache(ftup);
}
if (!OidIsValid(funcid))
{
/* Didn't find a function, so now try (type, int4, bool) */
oid_array[2] = BOOLOID;
*nargs = 3;
ftup = SearchSysCache(PROCNAMENSP,
CStringGetDatum(typname),
Int16GetDatum(3),
PointerGetDatum(oid_array),
ObjectIdGetDatum(typnamespace));
if (HeapTupleIsValid(ftup))
{
Form_pg_proc pform = (Form_pg_proc) GETSTRUCT(ftup);
/* Make sure the function's result type is as expected */
if (pform->prorettype == typeId && !pform->proretset &&
!pform->proisagg)
{
/* Okay to use it */
funcid = HeapTupleGetOid(ftup);
}
ReleaseSysCache(ftup);
}
}
ReleaseSysCache(targetType);
/*
* Now, if we did find a coercion function for an array element type,
* report array_length_coerce() as the function to use. We know it
* takes three arguments always.
*/
if (isArray && OidIsValid(funcid))
{
funcid = F_ARRAY_LENGTH_COERCE;
*nargs = 3;
}
return funcid;
}
@ -905,7 +1103,7 @@ find_typmod_coercion_function(Oid typeId)
* The argument expressions must have been transformed already.
*/
static Node *
build_func_call(Oid funcid, Oid rettype, List *args)
build_func_call(Oid funcid, Oid rettype, List *args, CoercionForm fformat)
{
Func *funcnode;
Expr *expr;
@ -914,6 +1112,7 @@ build_func_call(Oid funcid, Oid rettype, List *args)
funcnode->funcid = funcid;
funcnode->funcresulttype = rettype;
funcnode->funcretset = false; /* only possible case here */
funcnode->funcformat = fformat;
funcnode->func_fcache = NULL;
expr = makeNode(Expr);