PostgreSQL/src/backend/commands/functioncmds.c
Bruce Momjian b0f5086e41 oid is needed, it is added at the end of the struct (after the null
bitmap, if present).

Per Tom Lane's suggestion the information whether a tuple has an oid
or not is carried in the tuple descriptor.  For debugging reasons
tdhasoid is of type char, not bool.  There are predefined values for
WITHOID, WITHOUTOID and UNDEFOID.

This patch has been generated against a cvs snapshot from last week
and I don't expect it to apply cleanly to current sources.  While I
post it here for public review, I'm working on a new version against a
current snapshot.  (There's been heavy activity recently; hope to
catch up some day ...)

This is a long patch;  if it is too hard to swallow, I can provide it
in smaller pieces:

Part 1:  Accessor macros
Part 2:  tdhasoid in TupDesc
Part 3:  Regression test
Part 4:  Parameter withoid to heap_addheader
Part 5:  Eliminate t_oid from HeapTupleHeader

Part 2 is the most hairy part because of changes in the executor and
even in the parser;  the other parts are straightforward.

Up to part 4 the patched postmaster stays binary compatible to
databases created with an unpatched version.  Part 5 is small (100
lines) and finally breaks compatibility.

Manfred Koizar
2002-07-20 05:16:59 +00:00

840 lines
22 KiB
C

/*-------------------------------------------------------------------------
*
* functioncmds.c
*
* Routines for CREATE and DROP FUNCTION commands
*
* Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/commands/functioncmds.c,v 1.10 2002/07/20 05:16:57 momjian Exp $
*
* DESCRIPTION
* These routines take the parse tree and pick out the
* appropriate arguments/flags, and pass the results to the
* corresponding "FooDefine" routines (in src/catalog) that do
* the actual catalog-munging. These routines also verify permission
* of the user to execute the command.
*
* NOTES
* These things must be defined and committed in the following order:
* "create function":
* input/output, recv/send procedures
* "create type":
* type
* "create operator":
* operators
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "access/heapam.h"
#include "catalog/catname.h"
#include "catalog/dependency.h"
#include "catalog/indexing.h"
#include "catalog/namespace.h"
#include "catalog/pg_cast.h"
#include "catalog/pg_language.h"
#include "catalog/pg_proc.h"
#include "catalog/pg_type.h"
#include "commands/defrem.h"
#include "miscadmin.h"
#include "optimizer/cost.h"
#include "parser/parse_func.h"
#include "parser/parse_type.h"
#include "utils/acl.h"
#include "utils/fmgroids.h"
#include "utils/lsyscache.h"
#include "utils/syscache.h"
/*
* Examine the "returns" clause returnType of the CREATE FUNCTION statement
* and return information about it as *prorettype_p and *returnsSet.
*
* This is more complex than the average typename lookup because we want to
* allow a shell type to be used, or even created if the specified return type
* doesn't exist yet. (Without this, there's no way to define the I/O procs
* for a new type.) But SQL function creation won't cope, so error out if
* the target language is SQL.
*/
static void
compute_return_type(TypeName *returnType, Oid languageOid,
Oid *prorettype_p, bool *returnsSet_p)
{
Oid rettype;
rettype = LookupTypeName(returnType);
if (OidIsValid(rettype))
{
if (!get_typisdefined(rettype))
{
if (languageOid == SQLlanguageId)
elog(ERROR, "SQL functions cannot return shell types");
else
elog(WARNING, "Return type \"%s\" is only a shell",
TypeNameToString(returnType));
}
}
else
{
char *typnam = TypeNameToString(returnType);
if (strcmp(typnam, "opaque") == 0)
rettype = InvalidOid;
else
{
Oid namespaceId;
AclResult aclresult;
char *typname;
if (languageOid == SQLlanguageId)
elog(ERROR, "Type \"%s\" does not exist", typnam);
elog(WARNING, "ProcedureCreate: type %s is not yet defined",
typnam);
namespaceId = QualifiedNameGetCreationNamespace(returnType->names,
&typname);
aclresult = pg_namespace_aclcheck(namespaceId, GetUserId(),
ACL_CREATE);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, get_namespace_name(namespaceId));
rettype = TypeShellMake(typname, namespaceId);
if (!OidIsValid(rettype))
elog(ERROR, "could not create type %s", typnam);
}
}
*prorettype_p = rettype;
*returnsSet_p = returnType->setof;
}
/*
* Interpret the argument-types list of the CREATE FUNCTION statement.
*/
static int
compute_parameter_types(List *argTypes, Oid languageOid,
Oid *parameterTypes)
{
int parameterCount = 0;
List *x;
MemSet(parameterTypes, 0, FUNC_MAX_ARGS * sizeof(Oid));
foreach(x, argTypes)
{
TypeName *t = (TypeName *) lfirst(x);
Oid toid;
if (parameterCount >= FUNC_MAX_ARGS)
elog(ERROR, "functions cannot have more than %d arguments",
FUNC_MAX_ARGS);
toid = LookupTypeName(t);
if (OidIsValid(toid))
{
if (!get_typisdefined(toid))
elog(WARNING, "Argument type \"%s\" is only a shell",
TypeNameToString(t));
}
else
{
char *typnam = TypeNameToString(t);
if (strcmp(typnam, "opaque") == 0)
{
if (languageOid == SQLlanguageId)
elog(ERROR, "SQL functions cannot have arguments of type \"opaque\"");
toid = InvalidOid;
}
else
elog(ERROR, "Type \"%s\" does not exist", typnam);
}
if (t->setof)
elog(ERROR, "functions cannot accept set arguments");
parameterTypes[parameterCount++] = toid;
}
return parameterCount;
}
/*
* Dissect the list of options assembled in gram.y into function
* attributes.
*/
static void
compute_attributes_sql_style(const List *options,
List **as,
char **language,
char *volatility_p,
bool *strict_p,
bool *security_definer)
{
const List *option;
DefElem *as_item = NULL;
DefElem *language_item = NULL;
DefElem *volatility_item = NULL;
DefElem *strict_item = NULL;
DefElem *security_item = NULL;
foreach(option, options)
{
DefElem *defel = (DefElem *) lfirst(option);
if (strcmp(defel->defname, "as")==0)
{
if (as_item)
elog(ERROR, "conflicting or redundant options");
as_item = defel;
}
else if (strcmp(defel->defname, "language")==0)
{
if (language_item)
elog(ERROR, "conflicting or redundant options");
language_item = defel;
}
else if (strcmp(defel->defname, "volatility")==0)
{
if (volatility_item)
elog(ERROR, "conflicting or redundant options");
volatility_item = defel;
}
else if (strcmp(defel->defname, "strict")==0)
{
if (strict_item)
elog(ERROR, "conflicting or redundant options");
strict_item = defel;
}
else if (strcmp(defel->defname, "security")==0)
{
if (security_item)
elog(ERROR, "conflicting or redundant options");
security_item = defel;
}
else
elog(ERROR, "invalid CREATE FUNCTION option");
}
if (as_item)
*as = (List *)as_item->arg;
else
elog(ERROR, "no function body specified");
if (language_item)
*language = strVal(language_item->arg);
else
elog(ERROR, "no language specified");
if (volatility_item)
{
if (strcmp(strVal(volatility_item->arg), "immutable")==0)
*volatility_p = PROVOLATILE_IMMUTABLE;
else if (strcmp(strVal(volatility_item->arg), "stable")==0)
*volatility_p = PROVOLATILE_STABLE;
else if (strcmp(strVal(volatility_item->arg), "volatile")==0)
*volatility_p = PROVOLATILE_VOLATILE;
else
elog(ERROR, "invalid volatility");
}
if (strict_item)
*strict_p = intVal(strict_item->arg);
if (security_item)
*security_definer = intVal(security_item->arg);
}
/*-------------
* Interpret the parameters *parameters and return their contents as
* *byte_pct_p, etc.
*
* These parameters supply optional information about a function.
* All have defaults if not specified.
*
* Note: currently, only two of these parameters actually do anything:
*
* * isStrict means the function should not be called when any NULL
* inputs are present; instead a NULL result value should be assumed.
*
* * volatility tells the optimizer whether the function's result can
* be assumed to be repeatable over multiple evaluations.
*
* The other four parameters are not used anywhere. They used to be
* used in the "expensive functions" optimizer, but that's been dead code
* for a long time.
*------------
*/
static void
compute_attributes_with_style(List *parameters,
int32 *byte_pct_p, int32 *perbyte_cpu_p,
int32 *percall_cpu_p, int32 *outin_ratio_p,
bool *isStrict_p,
char *volatility_p)
{
List *pl;
foreach(pl, parameters)
{
DefElem *param = (DefElem *) lfirst(pl);
if (strcasecmp(param->defname, "isstrict") == 0)
*isStrict_p = true;
else if (strcasecmp(param->defname, "isimmutable") == 0)
*volatility_p = PROVOLATILE_IMMUTABLE;
else if (strcasecmp(param->defname, "isstable") == 0)
*volatility_p = PROVOLATILE_STABLE;
else if (strcasecmp(param->defname, "isvolatile") == 0)
*volatility_p = PROVOLATILE_VOLATILE;
else if (strcasecmp(param->defname, "iscachable") == 0)
{
/* obsolete spelling of isImmutable */
*volatility_p = PROVOLATILE_IMMUTABLE;
}
else if (strcasecmp(param->defname, "trusted") == 0)
{
/*
* we don't have untrusted functions any more. The 4.2
* implementation is lousy anyway so I took it out. -ay 10/94
*/
elog(ERROR, "untrusted function has been decommissioned.");
}
else if (strcasecmp(param->defname, "byte_pct") == 0)
*byte_pct_p = (int) defGetNumeric(param);
else if (strcasecmp(param->defname, "perbyte_cpu") == 0)
*perbyte_cpu_p = (int) defGetNumeric(param);
else if (strcasecmp(param->defname, "percall_cpu") == 0)
*percall_cpu_p = (int) defGetNumeric(param);
else if (strcasecmp(param->defname, "outin_ratio") == 0)
*outin_ratio_p = (int) defGetNumeric(param);
else
elog(WARNING, "Unrecognized function attribute '%s' ignored",
param->defname);
}
}
/*
* For a dynamically linked C language object, the form of the clause is
*
* AS <object file name> [, <link symbol name> ]
*
* In all other cases
*
* AS <object reference, or sql code>
*
*/
static void
interpret_AS_clause(Oid languageOid, const char *languageName, const List *as,
char **prosrc_str_p, char **probin_str_p)
{
Assert(as != NIL);
if (languageOid == ClanguageId)
{
/*
* For "C" language, store the file name in probin and, when
* given, the link symbol name in prosrc.
*/
*probin_str_p = strVal(lfirst(as));
if (lnext(as) == NULL)
*prosrc_str_p = "-";
else
*prosrc_str_p = strVal(lsecond(as));
}
else
{
/* Everything else wants the given string in prosrc. */
*prosrc_str_p = strVal(lfirst(as));
*probin_str_p = "-";
if (lnext(as) != NIL)
elog(ERROR, "CREATE FUNCTION: only one AS item needed for %s language",
languageName);
}
}
/*
* CreateFunction
* Execute a CREATE FUNCTION utility statement.
*/
void
CreateFunction(CreateFunctionStmt *stmt)
{
char *probin_str;
char *prosrc_str;
Oid prorettype;
bool returnsSet;
char *language;
char languageName[NAMEDATALEN];
Oid languageOid;
Oid languageValidator;
char *funcname;
Oid namespaceId;
AclResult aclresult;
int parameterCount;
Oid parameterTypes[FUNC_MAX_ARGS];
int32 byte_pct,
perbyte_cpu,
percall_cpu,
outin_ratio;
bool isStrict,
security;
char volatility;
HeapTuple languageTuple;
Form_pg_language languageStruct;
List *as_clause;
/* Convert list of names to a name and namespace */
namespaceId = QualifiedNameGetCreationNamespace(stmt->funcname,
&funcname);
/* Check we have creation rights in target namespace */
aclresult = pg_namespace_aclcheck(namespaceId, GetUserId(), ACL_CREATE);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, get_namespace_name(namespaceId));
/* defaults attributes */
byte_pct = BYTE_PCT;
perbyte_cpu = PERBYTE_CPU;
percall_cpu = PERCALL_CPU;
outin_ratio = OUTIN_RATIO;
isStrict = false;
security = false;
volatility = PROVOLATILE_VOLATILE;
/* override attributes from explicit list */
compute_attributes_sql_style(stmt->options,
&as_clause, &language, &volatility, &isStrict, &security);
/* Convert language name to canonical case */
case_translate_language_name(language, languageName);
/* Look up the language and validate permissions */
languageTuple = SearchSysCache(LANGNAME,
PointerGetDatum(languageName),
0, 0, 0);
if (!HeapTupleIsValid(languageTuple))
elog(ERROR, "language \"%s\" does not exist", languageName);
languageOid = HeapTupleGetOid(languageTuple);
languageStruct = (Form_pg_language) GETSTRUCT(languageTuple);
if (languageStruct->lanpltrusted)
{
/* if trusted language, need USAGE privilege */
AclResult aclresult;
aclresult = pg_language_aclcheck(languageOid, GetUserId(), ACL_USAGE);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, NameStr(languageStruct->lanname));
}
else
{
/* if untrusted language, must be superuser */
if (!superuser())
aclcheck_error(ACLCHECK_NO_PRIV, NameStr(languageStruct->lanname));
}
languageValidator = languageStruct->lanvalidator;
ReleaseSysCache(languageTuple);
/*
* Convert remaining parameters of CREATE to form wanted by
* ProcedureCreate.
*/
compute_return_type(stmt->returnType, languageOid,
&prorettype, &returnsSet);
parameterCount = compute_parameter_types(stmt->argTypes, languageOid,
parameterTypes);
compute_attributes_with_style(stmt->withClause,
&byte_pct, &perbyte_cpu, &percall_cpu,
&outin_ratio, &isStrict, &volatility);
interpret_AS_clause(languageOid, languageName, as_clause,
&prosrc_str, &probin_str);
if (languageOid == INTERNALlanguageId)
{
/*
* In PostgreSQL versions before 6.5, the SQL name of the
* created function could not be different from the internal
* name, and "prosrc" wasn't used. So there is code out there
* that does CREATE FUNCTION xyz AS '' LANGUAGE 'internal'.
* To preserve some modicum of backwards compatibility, accept
* an empty "prosrc" value as meaning the supplied SQL
* function name.
*/
if (strlen(prosrc_str) == 0)
prosrc_str = funcname;
}
if (languageOid == ClanguageId)
{
/* If link symbol is specified as "-", substitute procedure name */
if (strcmp(prosrc_str, "-") == 0)
prosrc_str = funcname;
}
/*
* And now that we have all the parameters, and know we're permitted
* to do so, go ahead and create the function.
*/
ProcedureCreate(funcname,
namespaceId,
stmt->replace,
returnsSet,
prorettype,
languageOid,
languageValidator,
prosrc_str, /* converted to text later */
probin_str, /* converted to text later */
false, /* not an aggregate */
security,
isStrict,
volatility,
byte_pct,
perbyte_cpu,
percall_cpu,
outin_ratio,
parameterCount,
parameterTypes);
}
/*
* RemoveFunction
* Deletes a function.
*/
void
RemoveFunction(RemoveFuncStmt *stmt)
{
List *functionName = stmt->funcname;
List *argTypes = stmt->args; /* list of TypeName nodes */
Oid funcOid;
HeapTuple tup;
ObjectAddress object;
/*
* Find the function, do permissions and validity checks
*/
funcOid = LookupFuncNameTypeNames(functionName, argTypes,
true, "RemoveFunction");
tup = SearchSysCache(PROCOID,
ObjectIdGetDatum(funcOid),
0, 0, 0);
if (!HeapTupleIsValid(tup)) /* should not happen */
elog(ERROR, "RemoveFunction: couldn't find tuple for function %s",
NameListToString(functionName));
/* Permission check: must own func or its namespace */
if (!pg_proc_ownercheck(funcOid, GetUserId()) &&
!pg_namespace_ownercheck(((Form_pg_proc) GETSTRUCT(tup))->pronamespace,
GetUserId()))
aclcheck_error(ACLCHECK_NOT_OWNER, NameListToString(functionName));
if (((Form_pg_proc) GETSTRUCT(tup))->proisagg)
elog(ERROR, "RemoveFunction: function '%s' is an aggregate"
"\n\tUse DROP AGGREGATE to remove it",
NameListToString(functionName));
if (((Form_pg_proc) GETSTRUCT(tup))->prolang == INTERNALlanguageId)
{
/* "Helpful" WARNING when removing a builtin function ... */
elog(WARNING, "Removing built-in function \"%s\"",
NameListToString(functionName));
}
ReleaseSysCache(tup);
/*
* Do the deletion
*/
object.classId = RelOid_pg_proc;
object.objectId = funcOid;
object.objectSubId = 0;
performDeletion(&object, stmt->behavior);
}
/*
* Guts of function deletion.
*
* Note: this is also used for aggregate deletion, since the OIDs of
* both functions and aggregates point to pg_proc.
*/
void
RemoveFunctionById(Oid funcOid)
{
Relation relation;
HeapTuple tup;
bool isagg;
/*
* Delete the pg_proc tuple.
*/
relation = heap_openr(ProcedureRelationName, RowExclusiveLock);
tup = SearchSysCache(PROCOID,
ObjectIdGetDatum(funcOid),
0, 0, 0);
if (!HeapTupleIsValid(tup)) /* should not happen */
elog(ERROR, "RemoveFunctionById: couldn't find tuple for function %u",
funcOid);
isagg = ((Form_pg_proc) GETSTRUCT(tup))->proisagg;
simple_heap_delete(relation, &tup->t_self);
ReleaseSysCache(tup);
heap_close(relation, RowExclusiveLock);
/*
* If there's a pg_aggregate tuple, delete that too.
*/
if (isagg)
{
relation = heap_openr(AggregateRelationName, RowExclusiveLock);
tup = SearchSysCache(AGGFNOID,
ObjectIdGetDatum(funcOid),
0, 0, 0);
if (!HeapTupleIsValid(tup)) /* should not happen */
elog(ERROR, "RemoveFunctionById: couldn't find pg_aggregate tuple for %u",
funcOid);
simple_heap_delete(relation, &tup->t_self);
ReleaseSysCache(tup);
heap_close(relation, RowExclusiveLock);
}
}
/*
* CREATE CAST
*/
void
CreateCast(CreateCastStmt *stmt)
{
Oid sourcetypeid;
Oid targettypeid;
Oid funcid;
HeapTuple tuple;
Relation relation;
Form_pg_proc procstruct;
Datum values[Natts_pg_proc];
char nulls[Natts_pg_proc];
int i;
ObjectAddress myself,
referenced;
sourcetypeid = LookupTypeName(stmt->sourcetype);
if (!OidIsValid(sourcetypeid))
elog(ERROR, "source data type %s does not exist",
TypeNameToString(stmt->sourcetype));
targettypeid = LookupTypeName(stmt->targettype);
if (!OidIsValid(targettypeid))
elog(ERROR, "target data type %s does not exist",
TypeNameToString(stmt->targettype));
if (sourcetypeid == targettypeid)
elog(ERROR, "source data type and target data type are the same");
relation = heap_openr(CastRelationName, RowExclusiveLock);
tuple = SearchSysCache(CASTSOURCETARGET,
ObjectIdGetDatum(sourcetypeid),
ObjectIdGetDatum(targettypeid),
0, 0);
if (HeapTupleIsValid(tuple))
elog(ERROR, "cast from data type %s to data type %s already exists",
TypeNameToString(stmt->sourcetype),
TypeNameToString(stmt->targettype));
if (stmt->func != NULL)
{
funcid = LookupFuncNameTypeNames(stmt->func->funcname, stmt->func->funcargs, false, "CreateCast");
if(!pg_proc_ownercheck(funcid, GetUserId()))
elog(ERROR, "permission denied");
tuple = SearchSysCache(PROCOID, ObjectIdGetDatum(funcid), 0, 0, 0);
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cache lookup of function %u failed", funcid);
procstruct = (Form_pg_proc) GETSTRUCT(tuple);
if (procstruct->pronargs != 1)
elog(ERROR, "cast function must take 1 argument");
if (procstruct->proargtypes[0] != sourcetypeid)
elog(ERROR, "argument of cast function must match source data type");
if (procstruct->prorettype != targettypeid)
elog(ERROR, "return data type of cast function must match target data type");
if (procstruct->provolatile != PROVOLATILE_IMMUTABLE)
elog(ERROR, "cast function must be immutable");
if (procstruct->proisagg)
elog(ERROR, "cast function must not be an aggregate function");
if (procstruct->proretset)
elog(ERROR, "cast function must be not return a set");
ReleaseSysCache(tuple);
}
else
{
/* indicates binary compatibility */
if (!pg_type_ownercheck(sourcetypeid, GetUserId())
|| !pg_type_ownercheck(targettypeid, GetUserId()))
elog(ERROR, "permission denied");
funcid = 0;
}
/* ready to go */
values[Anum_pg_cast_castsource-1] = ObjectIdGetDatum(sourcetypeid);
values[Anum_pg_cast_casttarget-1] = ObjectIdGetDatum(targettypeid);
values[Anum_pg_cast_castfunc-1] = ObjectIdGetDatum(funcid);
values[Anum_pg_cast_castimplicit-1] = BoolGetDatum(stmt->implicit);
for (i = 0; i < Natts_pg_cast; ++i)
nulls[i] = ' ';
tuple = heap_formtuple(RelationGetDescr(relation), values, nulls);
simple_heap_insert(relation, tuple);
if (RelationGetForm(relation)->relhasindex)
{
Relation idescs[Num_pg_cast_indices];
CatalogOpenIndices(Num_pg_cast_indices, Name_pg_cast_indices, idescs);
CatalogIndexInsert(idescs, Num_pg_cast_indices, relation, tuple);
CatalogCloseIndices(Num_pg_cast_indices, idescs);
}
myself.classId = get_system_catalog_relid(CastRelationName);
myself.objectId = tuple->t_data->t_oid;
myself.objectSubId = 0;
/* dependency on source type */
referenced.classId = RelOid_pg_type;
referenced.objectId = sourcetypeid;
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
/* dependency on target type */
referenced.classId = RelOid_pg_type;
referenced.objectId = targettypeid;
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
/* dependency on function */
if (OidIsValid(funcid))
{
referenced.classId = RelOid_pg_proc;
referenced.objectId = funcid;
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
}
heap_freetuple(tuple);
heap_close(relation, RowExclusiveLock);
}
/*
* DROP CAST
*/
void
DropCast(DropCastStmt *stmt)
{
Oid sourcetypeid;
Oid targettypeid;
HeapTuple tuple;
Form_pg_cast caststruct;
ObjectAddress object;
sourcetypeid = LookupTypeName(stmt->sourcetype);
if (!OidIsValid(sourcetypeid))
elog(ERROR, "source data type %s does not exist",
TypeNameToString(stmt->sourcetype));
targettypeid = LookupTypeName(stmt->targettype);
if (!OidIsValid(targettypeid))
elog(ERROR, "target data type %s does not exist",
TypeNameToString(stmt->targettype));
tuple = SearchSysCache(CASTSOURCETARGET,
ObjectIdGetDatum(sourcetypeid),
ObjectIdGetDatum(targettypeid),
0, 0);
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cast from type %s to type %s does not exist",
TypeNameToString(stmt->sourcetype),
TypeNameToString(stmt->targettype));
/* Permission check */
caststruct = (Form_pg_cast) GETSTRUCT(tuple);
if (caststruct->castfunc != InvalidOid)
{
if(!pg_proc_ownercheck(caststruct->castfunc, GetUserId()))
elog(ERROR, "permission denied");
}
else
{
if (!pg_type_ownercheck(sourcetypeid, GetUserId())
|| !pg_type_ownercheck(targettypeid, GetUserId()))
elog(ERROR, "permission denied");
}
ReleaseSysCache(tuple);
/*
* Do the deletion
*/
object.classId = get_system_catalog_relid(CastRelationName);
object.objectId = tuple->t_data->t_oid;
object.objectSubId = 0;
performDeletion(&object, stmt->behavior);
}
void
DropCastById(Oid castOid)
{
Relation relation;
ScanKeyData scankey;
HeapScanDesc scan;
HeapTuple tuple;
relation = heap_openr(CastRelationName, RowExclusiveLock);
ScanKeyEntryInitialize(&scankey, 0x0,
ObjectIdAttributeNumber, F_OIDEQ,
ObjectIdGetDatum(castOid));
scan = heap_beginscan(relation, SnapshotNow, 1, &scankey);
tuple = heap_getnext(scan, ForwardScanDirection);
if (HeapTupleIsValid(tuple))
simple_heap_delete(relation, &tuple->t_self);
else
elog(ERROR, "could not find tuple for cast %u", castOid);
heap_endscan(scan);
heap_close(relation, RowExclusiveLock);
}