rdelaage
/
postgresql
mirror of https://git.postgresql.org/git/postgresql.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity
postgresql/src/backend/catalog/pg_aggregate.c

405 lines
12 KiB
C
Raw Blame History

/*-------------------------------------------------------------------------
*
* pg_aggregate.c
* routines to support manipulation of the pg_aggregate relation
*
* Portions Copyright (c) 1996-2013, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* src/backend/catalog/pg_aggregate.c
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "access/heapam.h"
#include "access/htup_details.h"
#include "catalog/dependency.h"
#include "catalog/indexing.h"
#include "catalog/pg_aggregate.h"
#include "catalog/pg_language.h"
#include "catalog/pg_operator.h"
#include "catalog/pg_proc.h"
#include "catalog/pg_proc_fn.h"
#include "catalog/pg_type.h"
#include "miscadmin.h"
#include "parser/parse_coerce.h"
#include "parser/parse_func.h"
#include "parser/parse_oper.h"
#include "utils/acl.h"
#include "utils/builtins.h"
#include "utils/lsyscache.h"
#include "utils/rel.h"
#include "utils/syscache.h"
static Oid lookup_agg_function(List *fnName, int nargs, Oid *input_types,
Oid *rettype);
/*
* AggregateCreate
*/
Oid
AggregateCreate(const char *aggName,
Oid aggNamespace,
int numArgs,
oidvector *parameterTypes,
Datum allParameterTypes,
Datum parameterModes,
Datum parameterNames,
List *parameterDefaults,
List *aggtransfnName,
List *aggfinalfnName,
List *aggsortopName,
Oid aggTransType,
const char *agginitval)
{
Relation aggdesc;
HeapTuple tup;
bool nulls[Natts_pg_aggregate];
Datum values[Natts_pg_aggregate];
Form_pg_proc proc;
Oid transfn;
Oid finalfn = InvalidOid; /* can be omitted */
Oid sortop = InvalidOid; /* can be omitted */
Oid *aggArgTypes = parameterTypes->values;
bool hasPolyArg;
bool hasInternalArg;
Oid rettype;
Oid finaltype;
Oid *fnArgs;
int nargs_transfn;
Oid procOid;
TupleDesc tupDesc;
int i;
ObjectAddress myself,
referenced;
AclResult aclresult;
/* sanity checks (caller should have caught these) */
if (!aggName)
elog(ERROR, "no aggregate name supplied");
if (!aggtransfnName)
elog(ERROR, "aggregate must have a transition function");
/* check for polymorphic and INTERNAL arguments */
hasPolyArg = false;
hasInternalArg = false;
for (i = 0; i < numArgs; i++)
{
if (IsPolymorphicType(aggArgTypes[i]))
hasPolyArg = true;
else if (aggArgTypes[i] == INTERNALOID)
hasInternalArg = true;
}
/*
* If transtype is polymorphic, must have polymorphic argument also; else
* we will have no way to deduce the actual transtype.
*/
if (IsPolymorphicType(aggTransType) && !hasPolyArg)
ereport(ERROR,
(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
errmsg("cannot determine transition data type"),
errdetail("An aggregate using a polymorphic transition type must have at least one polymorphic argument.")));
/* find the transfn */
nargs_transfn = numArgs + 1;
fnArgs = (Oid *) palloc(nargs_transfn * sizeof(Oid));
fnArgs[0] = aggTransType;
memcpy(fnArgs + 1, aggArgTypes, numArgs * sizeof(Oid));
transfn = lookup_agg_function(aggtransfnName, nargs_transfn, fnArgs,
&rettype);
/*
* Return type of transfn (possibly after refinement by
* enforce_generic_type_consistency, if transtype isn't polymorphic) must
* exactly match declared transtype.
*
* In the non-polymorphic-transtype case, it might be okay to allow a
* rettype that's binary-coercible to transtype, but I'm not quite
* convinced that it's either safe or useful. When transtype is
* polymorphic we *must* demand exact equality.
*/
if (rettype != aggTransType)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("return type of transition function %s is not %s",
NameListToString(aggtransfnName),
format_type_be(aggTransType))));
tup = SearchSysCache1(PROCOID, ObjectIdGetDatum(transfn));
if (!HeapTupleIsValid(tup))
elog(ERROR, "cache lookup failed for function %u", transfn);
proc = (Form_pg_proc) GETSTRUCT(tup);
/*
* If the transfn is strict and the initval is NULL, make sure first input
* type and transtype are the same (or at least binary-compatible), so
* that it's OK to use the first input value as the initial transValue.
*/
if (proc->proisstrict && agginitval == NULL)
{
if (numArgs < 1 ||
!IsBinaryCoercible(aggArgTypes[0], aggTransType))
ereport(ERROR,
(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
errmsg("must not omit initial value when transition function is strict and transition type is not compatible with input type")));
}
ReleaseSysCache(tup);
/* handle finalfn, if supplied */
if (aggfinalfnName)
{
fnArgs[0] = aggTransType;
finalfn = lookup_agg_function(aggfinalfnName, 1, fnArgs,
&finaltype);
}
else
{
/*
* If no finalfn, aggregate result type is type of the state value
*/
finaltype = aggTransType;
}
Assert(OidIsValid(finaltype));
/*
* If finaltype (i.e. aggregate return type) is polymorphic, inputs must
* be polymorphic also, else parser will fail to deduce result type.
* (Note: given the previous test on transtype and inputs, this cannot
* happen, unless someone has snuck a finalfn definition into the catalogs
* that itself violates the rule against polymorphic result with no
* polymorphic input.)
*/
if (IsPolymorphicType(finaltype) && !hasPolyArg)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("cannot determine result data type"),
errdetail("An aggregate returning a polymorphic type "
"must have at least one polymorphic argument.")));
/*
* Also, the return type can't be INTERNAL unless there's at least one
* INTERNAL argument. This is the same type-safety restriction we enforce
* for regular functions, but at the level of aggregates. We must test
* this explicitly because we allow INTERNAL as the transtype.
*/
if (finaltype == INTERNALOID && !hasInternalArg)
ereport(ERROR,
(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
errmsg("unsafe use of pseudo-type \"internal\""),
errdetail("A function returning \"internal\" must have at least one \"internal\" argument.")));
/* handle sortop, if supplied */
if (aggsortopName)
{
if (numArgs != 1)
ereport(ERROR,
(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
errmsg("sort operator can only be specified for single-argument aggregates")));
sortop = LookupOperName(NULL, aggsortopName,
aggArgTypes[0], aggArgTypes[0],
false, -1);
}
/*
* permission checks on used types
*/
for (i = 0; i < numArgs; i++)
{
aclresult = pg_type_aclcheck(aggArgTypes[i], GetUserId(), ACL_USAGE);
if (aclresult != ACLCHECK_OK)
aclcheck_error_type(aclresult, aggArgTypes[i]);
}
aclresult = pg_type_aclcheck(aggTransType, GetUserId(), ACL_USAGE);
if (aclresult != ACLCHECK_OK)
aclcheck_error_type(aclresult, aggTransType);
aclresult = pg_type_aclcheck(finaltype, GetUserId(), ACL_USAGE);
if (aclresult != ACLCHECK_OK)
aclcheck_error_type(aclresult, finaltype);
/*
* Everything looks okay. Try to create the pg_proc entry for the
* aggregate. (This could fail if there's already a conflicting entry.)
*/
procOid = ProcedureCreate(aggName,
aggNamespace,
false, /* no replacement */
false, /* doesn't return a set */
finaltype, /* returnType */
GetUserId(), /* proowner */
INTERNALlanguageId, /* languageObjectId */
InvalidOid, /* no validator */
"aggregate_dummy", /* placeholder proc */
NULL, /* probin */
true, /* isAgg */
false, /* isWindowFunc */
false, /* security invoker (currently not
* definable for agg) */
false, /* isLeakProof */
false, /* isStrict (not needed for agg) */
PROVOLATILE_IMMUTABLE, /* volatility (not
* needed for agg) */
parameterTypes, /* paramTypes */
allParameterTypes, /* allParamTypes */
parameterModes, /* parameterModes */
parameterNames, /* parameterNames */
parameterDefaults, /* parameterDefaults */
PointerGetDatum(NULL), /* proconfig */
1, /* procost */
0); /* prorows */
/*
* Okay to create the pg_aggregate entry.
*/
/* initialize nulls and values */
for (i = 0; i < Natts_pg_aggregate; i++)
{
nulls[i] = false;
values[i] = (Datum) NULL;
}
values[Anum_pg_aggregate_aggfnoid - 1] = ObjectIdGetDatum(procOid);
values[Anum_pg_aggregate_aggtransfn - 1] = ObjectIdGetDatum(transfn);
values[Anum_pg_aggregate_aggfinalfn - 1] = ObjectIdGetDatum(finalfn);
values[Anum_pg_aggregate_aggsortop - 1] = ObjectIdGetDatum(sortop);
values[Anum_pg_aggregate_aggtranstype - 1] = ObjectIdGetDatum(aggTransType);
if (agginitval)
values[Anum_pg_aggregate_agginitval - 1] = CStringGetTextDatum(agginitval);
else
nulls[Anum_pg_aggregate_agginitval - 1] = true;
aggdesc = heap_open(AggregateRelationId, RowExclusiveLock);
tupDesc = aggdesc->rd_att;
tup = heap_form_tuple(tupDesc, values, nulls);
simple_heap_insert(aggdesc, tup);
CatalogUpdateIndexes(aggdesc, tup);
heap_close(aggdesc, RowExclusiveLock);
/*
* Create dependencies for the aggregate (above and beyond those already
* made by ProcedureCreate). Note: we don't need an explicit dependency
* on aggTransType since we depend on it indirectly through transfn.
*/
myself.classId = ProcedureRelationId;
myself.objectId = procOid;
myself.objectSubId = 0;
/* Depends on transition function */
referenced.classId = ProcedureRelationId;
referenced.objectId = transfn;
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
/* Depends on final function, if any */
if (OidIsValid(finalfn))
{
referenced.classId = ProcedureRelationId;
referenced.objectId = finalfn;
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
}
/* Depends on sort operator, if any */
if (OidIsValid(sortop))
{
referenced.classId = OperatorRelationId;
referenced.objectId = sortop;
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
}
return procOid;
}
/*
* lookup_agg_function -- common code for finding both transfn and finalfn
*/
static Oid
lookup_agg_function(List *fnName,
int nargs,
Oid *input_types,
Oid *rettype)
{
Oid fnOid;
bool retset;
int nvargs;
Oid vatype;
Oid *true_oid_array;
FuncDetailCode fdresult;
AclResult aclresult;
int i;
/*
* func_get_detail looks up the function in the catalogs, does
* disambiguation for polymorphic functions, handles inheritance, and
* returns the funcid and type and set or singleton status of the
* function's return value. it also returns the true argument types to
* the function.
*/
fdresult = func_get_detail(fnName, NIL, NIL,
nargs, input_types, false, false,
&fnOid, rettype, &retset,
&nvargs, &vatype,
&true_oid_array, NULL);
/* only valid case is a normal function not returning a set */
if (fdresult != FUNCDETAIL_NORMAL || !OidIsValid(fnOid))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_FUNCTION),
errmsg("function %s does not exist",
func_signature_string(fnName, nargs,
NIL, input_types))));
if (retset)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("function %s returns a set",
func_signature_string(fnName, nargs,
NIL, input_types))));
/*
* If there are any polymorphic types involved, enforce consistency, and
* possibly refine the result type. It's OK if the result is still
* polymorphic at this point, though.
*/
*rettype = enforce_generic_type_consistency(input_types,
true_oid_array,
nargs,
*rettype,
true);
/*
* func_get_detail will find functions requiring run-time argument type
* coercion, but nodeAgg.c isn't prepared to deal with that
*/
for (i = 0; i < nargs; i++)
{
if (!IsPolymorphicType(true_oid_array[i]) &&
!IsBinaryCoercible(input_types[i], true_oid_array[i]))
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("function %s requires run-time type coercion",
func_signature_string(fnName, nargs,
NIL, true_oid_array))));
}
/* Check aggregate creator has permission to call the function */
aclresult = pg_proc_aclcheck(fnOid, GetUserId(), ACL_EXECUTE);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, ACL_KIND_PROC, get_func_name(fnOid));
return fnOid;
}
Reference in New Issue View Git Blame Copy Permalink