Thanks again, the reason is found. The following statement frees all the context for aggregation, including the transValue and tempTransValue: MemoryContextResetAndDeleteChildren(winstate->aggcontext);
-----Original Message----- From: Tom Lane [mailto:t...@sss.pgh.pa.us] Sent: 2012年8月22日 9:47 To: Wang, Chaoyong Cc: pgsql-hackers@postgresql.org Subject: Re: [HACKERS] problem when optimizing the window aggregation "Wang, Chaoyong" <chaoyong.w...@emc.com> writes: > I used the function datumCopy as following: > peraggstate->transValue = datumCopy(peraggstate->tempTransValue, > peraggstate->transtypeByVal, peraggstate->transtypeLen); You need to guard that with an is-null check, because datumCopy isn't designed to cope with null values. (Which is historical, I guess, but we're not likely to change it now.) If you look around you will find plenty of examples of this coding pattern. regards, tom lane -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
