mirror of
https://github.com/postgres/postgres.git
synced 2025-07-02 09:02:37 +03:00
Code review for DOMAIN patch.
This commit is contained in:
Tom Lane
122
src/backend/utils/cache/lsyscache.c
vendored
122
src/backend/utils/cache/lsyscache.c
vendored
@ -7,7 +7,7 @@
|
||||
* Portions Copyright (c) 1994, Regents of the University of California
|
||||
*
|
||||
* IDENTIFICATION
|
||||
* $Header: /cvsroot/pgsql/src/backend/utils/cache/lsyscache.c,v 1.63 2002/03/19 02:18:21 momjian Exp $
|
||||
* $Header: /cvsroot/pgsql/src/backend/utils/cache/lsyscache.c,v 1.64 2002/03/20 19:44:42 tgl Exp $
|
||||
*
|
||||
* NOTES
|
||||
* Eventually, the index information should go through here, too.
|
||||
@ -23,7 +23,7 @@
|
||||
#include "catalog/pg_shadow.h"
|
||||
#include "catalog/pg_statistic.h"
|
||||
#include "catalog/pg_type.h"
|
||||
#include "parser/parse_coerce.h"
|
||||
#include "nodes/makefuncs.h"
|
||||
#include "utils/array.h"
|
||||
#include "utils/builtins.h"
|
||||
#include "utils/lsyscache.h"
|
||||
@ -818,19 +818,19 @@ get_typstorage(Oid typid)
|
||||
|
||||
/*
|
||||
* get_typdefault
|
||||
*
|
||||
* Given a type OID, return the type's default value, if any.
|
||||
* Returns FALSE if there is no default (effectively, default is NULL).
|
||||
* The result points to palloc'd storage for pass-by-reference types.
|
||||
*
|
||||
* The result is a palloc'd expression node tree, or NULL if there
|
||||
* is no defined default for the datatype.
|
||||
*
|
||||
* NB: caller should be prepared to coerce result to correct datatype;
|
||||
* the returned expression tree might produce something of the wrong type.
|
||||
*/
|
||||
Node *
|
||||
get_typdefault(Oid typid, int32 atttypmod)
|
||||
get_typdefault(Oid typid)
|
||||
{
|
||||
HeapTuple typeTuple;
|
||||
Form_pg_type type;
|
||||
Oid typinput;
|
||||
Oid typbasetype;
|
||||
char typtype;
|
||||
Datum datum;
|
||||
bool isNull;
|
||||
Node *expr;
|
||||
@ -838,50 +838,104 @@ get_typdefault(Oid typid, int32 atttypmod)
|
||||
typeTuple = SearchSysCache(TYPEOID,
|
||||
ObjectIdGetDatum(typid),
|
||||
0, 0, 0);
|
||||
|
||||
if (!HeapTupleIsValid(typeTuple))
|
||||
elog(ERROR, "get_typdefault: failed to lookup type %u", typid);
|
||||
|
||||
type = (Form_pg_type) GETSTRUCT(typeTuple);
|
||||
|
||||
typinput = type->typinput;
|
||||
typbasetype = type->typbasetype;
|
||||
typtype = type->typtype;
|
||||
|
||||
/*
|
||||
* typdefaultbin is potentially null, so don't try to access it as a
|
||||
* struct field. Must do it the hard way with SysCacheGetAttr.
|
||||
* typdefault and typdefaultbin are potentially null, so don't try to
|
||||
* access 'em as struct fields. Must do it the hard way with
|
||||
* SysCacheGetAttr.
|
||||
*/
|
||||
datum = SysCacheGetAttr(TYPEOID,
|
||||
typeTuple,
|
||||
Anum_pg_type_typdefaultbin,
|
||||
&isNull);
|
||||
|
||||
ReleaseSysCache(typeTuple);
|
||||
if (isNull)
|
||||
return (Node *) NULL;
|
||||
if (!isNull)
|
||||
{
|
||||
/* We have an expression default */
|
||||
expr = stringToNode(DatumGetCString(DirectFunctionCall1(textout,
|
||||
datum)));
|
||||
}
|
||||
else
|
||||
{
|
||||
/* Perhaps we have a plain literal default */
|
||||
datum = SysCacheGetAttr(TYPEOID,
|
||||
typeTuple,
|
||||
Anum_pg_type_typdefault,
|
||||
&isNull);
|
||||
|
||||
/* Convert Datum to a Node */
|
||||
expr = stringToNode(DatumGetCString(
|
||||
DirectFunctionCall1(textout, datum)));
|
||||
if (!isNull)
|
||||
{
|
||||
char *strDefaultVal;
|
||||
|
||||
|
||||
/*
|
||||
* Ensure we goto the basetype before the domain type.
|
||||
*
|
||||
* Prevents scenarios like the below from failing:
|
||||
* CREATE DOMAIN dom text DEFAULT random();
|
||||
*
|
||||
*/
|
||||
if (typbasetype != InvalidOid) {
|
||||
expr = coerce_type(NULL, expr, typid,
|
||||
typbasetype, atttypmod);
|
||||
/* Convert text datum to C string */
|
||||
strDefaultVal = DatumGetCString(DirectFunctionCall1(textout,
|
||||
datum));
|
||||
/* Convert C string to a value of the given type */
|
||||
datum = OidFunctionCall3(type->typinput,
|
||||
CStringGetDatum(strDefaultVal),
|
||||
ObjectIdGetDatum(type->typelem),
|
||||
Int32GetDatum(-1));
|
||||
/* Build a Const node containing the value */
|
||||
expr = (Node *) makeConst(typid,
|
||||
type->typlen,
|
||||
datum,
|
||||
false,
|
||||
type->typbyval,
|
||||
false, /* not a set */
|
||||
false);
|
||||
pfree(strDefaultVal);
|
||||
}
|
||||
else
|
||||
{
|
||||
/* No default */
|
||||
expr = NULL;
|
||||
}
|
||||
}
|
||||
|
||||
ReleaseSysCache(typeTuple);
|
||||
|
||||
return expr;
|
||||
}
|
||||
|
||||
/*
|
||||
* getBaseType
|
||||
* If the given type is a domain, return its base type;
|
||||
* otherwise return the type's own OID.
|
||||
*/
|
||||
Oid
|
||||
getBaseType(Oid typid)
|
||||
{
|
||||
/*
|
||||
* We loop to find the bottom base type in a stack of domains.
|
||||
*/
|
||||
for (;;)
|
||||
{
|
||||
HeapTuple tup;
|
||||
Form_pg_type typTup;
|
||||
|
||||
tup = SearchSysCache(TYPEOID,
|
||||
ObjectIdGetDatum(typid),
|
||||
0, 0, 0);
|
||||
if (!HeapTupleIsValid(tup))
|
||||
elog(ERROR, "getBaseType: failed to lookup type %u", typid);
|
||||
typTup = (Form_pg_type) GETSTRUCT(tup);
|
||||
if (typTup->typtype != 'd')
|
||||
{
|
||||
/* Not a domain, so done */
|
||||
ReleaseSysCache(tup);
|
||||
break;
|
||||
}
|
||||
|
||||
typid = typTup->typbasetype;
|
||||
ReleaseSysCache(tup);
|
||||
}
|
||||
|
||||
return typid;
|
||||
}
|
||||
|
||||
/*
|
||||
* get_typavgwidth
|
||||
*
|
||||
|
||||
Reference in New Issue
Block a user