Is regression clean? Have you looked at how the member is used using some code browsing tool like cscope by examining it's every occurrence? PG uses simulated run time polymorphism a lot, so any Node should examined carefully from that angle too. Even after all of that if you think that it's not being used, you can submit a patch to community removing that member. Somebody from community reviewers will review and commit the patch if they find it correct and useful.
Read http://wiki.postgresql.org/wiki/Submitting_a_Patch before submitting the patch. On Fri, Apr 29, 2011 at 3:22 PM, Vaibhav Kaushal < vaibhavkaushal...@gmail.com> wrote: > I tried all aggregates - min,max,sum,count and avg. all are working. What > do you suggest now? > > > On Fri, Apr 29, 2011 at 11:30 AM, Ashutosh Bapat < > ashutosh.ba...@enterprisedb.com> wrote: > >> >> >> On Thu, Apr 28, 2011 at 4:21 PM, Vaibhav Kaushal < >> vaibhavkaushal...@gmail.com> wrote: >> >>> Thanks a lot. I was browsing the code and was thinking this would be the >>> most probable scenario. >>> >>> But, the point is that even after removing the args initialization part >>> in the ExecInitExpr for AggrefState, the sum() function is working. I >>> believe that is also a aggregate function! If yes, then how is it working if >>> I dd not allow the args to be initialized. The debugger says that >>> ExecEvalAggref was called and the results returned are true. >>> >>> >> Did you check the same thing with avg, or any statistical aggregates. Sum >> does not need all the aggregate infrastructure in place, for example >> finalisation function. May be after removing initialization part you want to >> run regression (or at least aggregates.sql) to see what it breaks. >> >> >>> Regards, >>> Vaibhav >>> >>> >>> On Thu, Apr 28, 2011 at 2:38 PM, Ashutosh Bapat < >>> ashutosh.ba...@enterprisedb.com> wrote: >>> >>>> The args in AggrefExprState, are used in the functions ExecAgg, >>>> ExecInitAgg and their minions to evaluate the aggregates. The >>>> ExecEvalAggref() merely retrieves the results of aggregation calculated >>>> during ExecAgg. >>>> >>>> >>>> On Tue, Apr 26, 2011 at 12:04 PM, Vaibhav Kaushal < >>>> vaibhavkaushal...@gmail.com> wrote: >>>> >>>>> Hello all, >>>>> >>>>> While examining the executor, I was wondering what the *args part of >>>>> AggrefExprState nodes contain. I found that the Aggref (Expr)'s args list >>>>> is a list of TargetEntry nodes. But the state node's args is initialized >>>>> in >>>>> ExecInitExpr as: >>>>> >>>>> astate->args = (List *) ExecInitExpr((Expr *) aggref->args, >>>>> parent); >>>>> >>>>> This would mean that the args is actually a ExprState node list with >>>>> one single item (the ExprState node / tree). I believe it potentially >>>>> contains the execution tree to determine the state / value of the aggref >>>>> (sub)expression. But then in the ExecEvalAggref function I do not see the >>>>> args coming into picture at all! I am also unable to find a call to some >>>>> function for executing the state node created in the args list. Also, no >>>>> value is being extracted from that node! Why is it so? >>>>> >>>>> For quick reference I am adding the function (may be you don't need it >>>>> but still... its a small one): >>>>> >>>>> /* ---------------------------------------------------------------- >>>>> * ExecEvalAggref >>>>> * >>>>> * Returns a Datum whose value is the value of the precomputed >>>>> * aggregate found in the given expression context. >>>>> * ---------------------------------------------------------------- >>>>> */ >>>>> static Datum >>>>> ExecEvalAggref(AggrefExprState *aggref, ExprContext *econtext, >>>>> bool *isNull, ExprDoneCond *isDone) >>>>> { >>>>> if (isDone) >>>>> *isDone = ExprSingleResult; >>>>> >>>>> if (econtext->ecxt_aggvalues == NULL) /* safety check */ >>>>> elog(ERROR, "no aggregates in this expression context"); >>>>> >>>>> *isNull = econtext->ecxt_aggnulls[aggref->aggno]; >>>>> return econtext->ecxt_aggvalues[aggref->aggno]; >>>>> } >>>>> >>>>> >>>>> What is the use of args in AggrefExprState node here? Is it there just >>>>> for some historical reason? >>>>> >>>>> Regards, >>>>> Vaibhav >>>>> >>>> >>>> >>>> >>>> -- >>>> Best Wishes, >>>> Ashutosh Bapat >>>> EntepriseDB Corporation >>>> The Enterprise Postgres Company >>>> >>>> >>> >> >> >> -- >> Best Wishes, >> Ashutosh Bapat >> EntepriseDB Corporation >> The Enterprise Postgres Company >> >> > -- Best Wishes, Ashutosh Bapat EntepriseDB Corporation The Enterprise Postgres Company
