Cleanup some aggregate code in the executor

Here we alter the code that calls build_pertrans_for_aggref() so that the
function no longer needs to special-case whether it's dealing with an
aggtransfn or an aggcombinefn.  This allows us to reuse the
build_aggregate_transfn_expr() function and just get rid of the
build_aggregate_combinefn_expr() completely.

All of the special case code that was in build_pertrans_for_aggref() has
been moved up to the calling functions.

This saves about a dozen lines of code in nodeAgg.c and a few dozen more
in parse_agg.c

Also, rename a few variables in nodeAgg.c to try to make it more clear
that we're working with either a aggtransfn or an aggcombinefn.  Some of
the old names would have you believe that we were always working with an
aggtransfn.

Discussion: https://postgr.es/m/CAApHDvptMQ9FmF0D67zC_w88yVnoNVR2+kkOQGUrCmdxWxLULQ@mail.gmail.com
This commit is contained in:
David Rowley 2021-07-04 18:47:31 +12:00
parent 792259591c
commit 63b1af9437
3 changed files with 118 additions and 155 deletions

View File

@ -461,10 +461,11 @@ static void hashagg_tapeinfo_release(HashTapeInfo *tapeinfo, int tapenum);
static Datum GetAggInitVal(Datum textInitVal, Oid transtype);
static void build_pertrans_for_aggref(AggStatePerTrans pertrans,
AggState *aggstate, EState *estate,
Aggref *aggref, Oid aggtransfn, Oid aggtranstype,
Oid aggserialfn, Oid aggdeserialfn,
Datum initValue, bool initValueIsNull,
Oid *inputTypes, int numArguments);
Aggref *aggref, Oid transfn_oid,
Oid aggtranstype, Oid aggserialfn,
Oid aggdeserialfn, Datum initValue,
bool initValueIsNull, Oid *inputTypes,
int numArguments);
/*
@ -3724,8 +3725,8 @@ ExecInitAgg(Agg *node, EState *estate, int eflags)
Aggref *aggref = lfirst(l);
AggStatePerAgg peragg;
AggStatePerTrans pertrans;
Oid inputTypes[FUNC_MAX_ARGS];
int numArguments;
Oid aggTransFnInputTypes[FUNC_MAX_ARGS];
int numAggTransFnArgs;
int numDirectArgs;
HeapTuple aggTuple;
Form_pg_aggregate aggform;
@ -3859,14 +3860,15 @@ ExecInitAgg(Agg *node, EState *estate, int eflags)
* could be different from the agg's declared input types, when the
* agg accepts ANY or a polymorphic type.
*/
numArguments = get_aggregate_argtypes(aggref, inputTypes);
numAggTransFnArgs = get_aggregate_argtypes(aggref,
aggTransFnInputTypes);
/* Count the "direct" arguments, if any */
numDirectArgs = list_length(aggref->aggdirectargs);
/* Detect how many arguments to pass to the finalfn */
if (aggform->aggfinalextra)
peragg->numFinalArgs = numArguments + 1;
peragg->numFinalArgs = numAggTransFnArgs + 1;
else
peragg->numFinalArgs = numDirectArgs + 1;
@ -3880,7 +3882,7 @@ ExecInitAgg(Agg *node, EState *estate, int eflags)
*/
if (OidIsValid(finalfn_oid))
{
build_aggregate_finalfn_expr(inputTypes,
build_aggregate_finalfn_expr(aggTransFnInputTypes,
peragg->numFinalArgs,
aggtranstype,
aggref->aggtype,
@ -3911,7 +3913,7 @@ ExecInitAgg(Agg *node, EState *estate, int eflags)
/*
* If this aggregation is performing state combines, then instead
* of using the transition function, we'll use the combine
* function
* function.
*/
if (DO_AGGSPLIT_COMBINE(aggstate->aggsplit))
{
@ -3924,8 +3926,7 @@ ExecInitAgg(Agg *node, EState *estate, int eflags)
else
transfn_oid = aggform->aggtransfn;
aclresult = pg_proc_aclcheck(transfn_oid, aggOwner,
ACL_EXECUTE);
aclresult = pg_proc_aclcheck(transfn_oid, aggOwner, ACL_EXECUTE);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, OBJECT_FUNCTION,
get_func_name(transfn_oid));
@ -3943,11 +3944,72 @@ ExecInitAgg(Agg *node, EState *estate, int eflags)
else
initValue = GetAggInitVal(textInitVal, aggtranstype);
build_pertrans_for_aggref(pertrans, aggstate, estate,
aggref, transfn_oid, aggtranstype,
serialfn_oid, deserialfn_oid,
initValue, initValueIsNull,
inputTypes, numArguments);
if (DO_AGGSPLIT_COMBINE(aggstate->aggsplit))
{
Oid combineFnInputTypes[] = {aggtranstype,
aggtranstype};
/*
* When combining there's only one input, the to-be-combined
* transition value. The transition value is not counted
* here.
*/
pertrans->numTransInputs = 1;
/* aggcombinefn always has two arguments of aggtranstype */
build_pertrans_for_aggref(pertrans, aggstate, estate,
aggref, transfn_oid, aggtranstype,
serialfn_oid, deserialfn_oid,
initValue, initValueIsNull,
combineFnInputTypes, 2);
/*
* Ensure that a combine function to combine INTERNAL states
* is not strict. This should have been checked during CREATE
* AGGREGATE, but the strict property could have been changed
* since then.
*/
if (pertrans->transfn.fn_strict && aggtranstype == INTERNALOID)
ereport(ERROR,
(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
errmsg("combine function with transition type %s must not be declared STRICT",
format_type_be(aggtranstype))));
}
else
{
/* Detect how many arguments to pass to the transfn */
if (AGGKIND_IS_ORDERED_SET(aggref->aggkind))
pertrans->numTransInputs = list_length(aggref->args);
else
pertrans->numTransInputs = numAggTransFnArgs;
build_pertrans_for_aggref(pertrans, aggstate, estate,
aggref, transfn_oid, aggtranstype,
serialfn_oid, deserialfn_oid,
initValue, initValueIsNull,
aggTransFnInputTypes,
numAggTransFnArgs);
/*
* If the transfn is strict and the initval is NULL, make sure
* input type and transtype are the same (or at least
* binary-compatible), so that it's OK to use the first
* aggregated input value as the initial transValue. This
* should have been checked at agg definition time, but we
* must check again in case the transfn's strictness property
* has been changed.
*/
if (pertrans->transfn.fn_strict && pertrans->initValueIsNull)
{
if (numAggTransFnArgs <= numDirectArgs ||
!IsBinaryCoercible(aggTransFnInputTypes[numDirectArgs],
aggtranstype))
ereport(ERROR,
(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
errmsg("aggregate %u needs to have compatible input type and transition type",
aggref->aggfnoid)));
}
}
}
else
pertrans->aggshared = true;
@ -4039,20 +4101,24 @@ ExecInitAgg(Agg *node, EState *estate, int eflags)
* Build the state needed to calculate a state value for an aggregate.
*
* This initializes all the fields in 'pertrans'. 'aggref' is the aggregate
* to initialize the state for. 'aggtransfn', 'aggtranstype', and the rest
* to initialize the state for. 'transfn_oid', 'aggtranstype', and the rest
* of the arguments could be calculated from 'aggref', but the caller has
* calculated them already, so might as well pass them.
*
* 'transfn_oid' may be either the Oid of the aggtransfn or the aggcombinefn.
*/
static void
build_pertrans_for_aggref(AggStatePerTrans pertrans,
AggState *aggstate, EState *estate,
Aggref *aggref,
Oid aggtransfn, Oid aggtranstype,
Oid transfn_oid, Oid aggtranstype,
Oid aggserialfn, Oid aggdeserialfn,
Datum initValue, bool initValueIsNull,
Oid *inputTypes, int numArguments)
{
int numGroupingSets = Max(aggstate->maxsets, 1);
Expr *transfnexpr;
int numTransArgs;
Expr *serialfnexpr = NULL;
Expr *deserialfnexpr = NULL;
ListCell *lc;
@ -4067,7 +4133,7 @@ build_pertrans_for_aggref(AggStatePerTrans pertrans,
pertrans->aggref = aggref;
pertrans->aggshared = false;
pertrans->aggCollation = aggref->inputcollid;
pertrans->transfn_oid = aggtransfn;
pertrans->transfn_oid = transfn_oid;
pertrans->serialfn_oid = aggserialfn;
pertrans->deserialfn_oid = aggdeserialfn;
pertrans->initValue = initValue;
@ -4081,111 +4147,34 @@ build_pertrans_for_aggref(AggStatePerTrans pertrans,
pertrans->aggtranstype = aggtranstype;
/* account for the current transition state */
numTransArgs = pertrans->numTransInputs + 1;
/*
* When combining states, we have no use at all for the aggregate
* function's transfn. Instead we use the combinefn. In this case, the
* transfn and transfn_oid fields of pertrans refer to the combine
* function rather than the transition function.
* Set up infrastructure for calling the transfn. Note that invtrans is
* not needed here.
*/
if (DO_AGGSPLIT_COMBINE(aggstate->aggsplit))
{
Expr *combinefnexpr;
size_t numTransArgs;
build_aggregate_transfn_expr(inputTypes,
numArguments,
numDirectArgs,
aggref->aggvariadic,
aggtranstype,
aggref->inputcollid,
transfn_oid,
InvalidOid,
&transfnexpr,
NULL);
/*
* When combining there's only one input, the to-be-combined added
* transition value from below (this node's transition value is
* counted separately).
*/
pertrans->numTransInputs = 1;
fmgr_info(transfn_oid, &pertrans->transfn);
fmgr_info_set_expr((Node *) transfnexpr, &pertrans->transfn);
/* account for the current transition state */
numTransArgs = pertrans->numTransInputs + 1;
build_aggregate_combinefn_expr(aggtranstype,
aggref->inputcollid,
aggtransfn,
&combinefnexpr);
fmgr_info(aggtransfn, &pertrans->transfn);
fmgr_info_set_expr((Node *) combinefnexpr, &pertrans->transfn);
pertrans->transfn_fcinfo =
(FunctionCallInfo) palloc(SizeForFunctionCallInfo(2));
InitFunctionCallInfoData(*pertrans->transfn_fcinfo,
&pertrans->transfn,
numTransArgs,
pertrans->aggCollation,
(void *) aggstate, NULL);
/*
* Ensure that a combine function to combine INTERNAL states is not
* strict. This should have been checked during CREATE AGGREGATE, but
* the strict property could have been changed since then.
*/
if (pertrans->transfn.fn_strict && aggtranstype == INTERNALOID)
ereport(ERROR,
(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
errmsg("combine function with transition type %s must not be declared STRICT",
format_type_be(aggtranstype))));
}
else
{
Expr *transfnexpr;
size_t numTransArgs;
/* Detect how many arguments to pass to the transfn */
if (AGGKIND_IS_ORDERED_SET(aggref->aggkind))
pertrans->numTransInputs = numInputs;
else
pertrans->numTransInputs = numArguments;
/* account for the current transition state */
numTransArgs = pertrans->numTransInputs + 1;
/*
* Set up infrastructure for calling the transfn. Note that
* invtransfn is not needed here.
*/
build_aggregate_transfn_expr(inputTypes,
numArguments,
numDirectArgs,
aggref->aggvariadic,
aggtranstype,
aggref->inputcollid,
aggtransfn,
InvalidOid,
&transfnexpr,
NULL);
fmgr_info(aggtransfn, &pertrans->transfn);
fmgr_info_set_expr((Node *) transfnexpr, &pertrans->transfn);
pertrans->transfn_fcinfo =
(FunctionCallInfo) palloc(SizeForFunctionCallInfo(numTransArgs));
InitFunctionCallInfoData(*pertrans->transfn_fcinfo,
&pertrans->transfn,
numTransArgs,
pertrans->aggCollation,
(void *) aggstate, NULL);
/*
* If the transfn is strict and the initval is NULL, make sure input
* type and transtype are the same (or at least binary-compatible), so
* that it's OK to use the first aggregated input value as the initial
* transValue. This should have been checked at agg definition time,
* but we must check again in case the transfn's strictness property
* has been changed.
*/
if (pertrans->transfn.fn_strict && pertrans->initValueIsNull)
{
if (numArguments <= numDirectArgs ||
!IsBinaryCoercible(inputTypes[numDirectArgs],
aggtranstype))
ereport(ERROR,
(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
errmsg("aggregate %u needs to have compatible input type and transition type",
aggref->aggfnoid)));
}
}
pertrans->transfn_fcinfo =
(FunctionCallInfo) palloc(SizeForFunctionCallInfo(numTransArgs));
InitFunctionCallInfoData(*pertrans->transfn_fcinfo,
&pertrans->transfn,
numTransArgs,
pertrans->aggCollation,
(void *) aggstate, NULL);
/* get info about the state value's datatype */
get_typlenbyval(aggtranstype,
@ -4276,6 +4265,9 @@ build_pertrans_for_aggref(AggStatePerTrans pertrans,
*/
Assert(aggstate->aggstrategy != AGG_HASHED && aggstate->aggstrategy != AGG_MIXED);
/* ORDER BY aggregates are not supported with partial aggregation */
Assert(!DO_AGGSPLIT_COMBINE(aggstate->aggsplit));
/* If we have only one input, we need its len/byval info. */
if (numInputs == 1)
{

View File

@ -1959,6 +1959,11 @@ resolve_aggregate_transtype(Oid aggfuncid,
* latter may be InvalidOid, however if invtransfn_oid is set then
* transfn_oid must also be set.
*
* transfn_oid may also be passed as the aggcombinefn when the *transfnexpr is
* to be used for a combine aggregate phase. We expect invtransfn_oid to be
* InvalidOid in this case since there is no such thing as an inverse
* combinefn.
*
* Pointers to the constructed trees are returned into *transfnexpr,
* *invtransfnexpr. If there is no invtransfn, the respective pointer is set
* to NULL. Since use of the invtransfn is optional, NULL may be passed for
@ -2021,35 +2026,6 @@ build_aggregate_transfn_expr(Oid *agg_input_types,
}
}
/*
* Like build_aggregate_transfn_expr, but creates an expression tree for the
* combine function of an aggregate, rather than the transition function.
*/
void
build_aggregate_combinefn_expr(Oid agg_state_type,
Oid agg_input_collation,
Oid combinefn_oid,
Expr **combinefnexpr)
{
Node *argp;
List *args;
FuncExpr *fexpr;
/* combinefn takes two arguments of the aggregate state type */
argp = make_agg_arg(agg_state_type, agg_input_collation);
args = list_make2(argp, argp);
fexpr = makeFuncExpr(combinefn_oid,
agg_state_type,
args,
InvalidOid,
agg_input_collation,
COERCE_EXPLICIT_CALL);
/* combinefn is currently never treated as variadic */
*combinefnexpr = (Expr *) fexpr;
}
/*
* Like build_aggregate_transfn_expr, but creates an expression tree for the
* serialization function of an aggregate.

View File

@ -46,11 +46,6 @@ extern void build_aggregate_transfn_expr(Oid *agg_input_types,
Expr **transfnexpr,
Expr **invtransfnexpr);
extern void build_aggregate_combinefn_expr(Oid agg_state_type,
Oid agg_input_collation,
Oid combinefn_oid,
Expr **combinefnexpr);
extern void build_aggregate_serialfn_expr(Oid serialfn_oid,
Expr **serialfnexpr);