Обсуждение: How to copy Datum
Hi,
I’m trying to reduce the re-computing of window aggregation. Here the AVG function for example.
The original window aggregation’s transition value(transValue) of AVG is an ArrayType, that contains two main values(sum, count).
Now, I’m using a temporary transition value (tempTransValue), and I need to copy tempTransValue to the original window aggregation’s transition value(transValue).
I used the function datumCopy as following:
peraggstate->transValue = datumCopy(peraggstate->tempTransValue, peraggstate->transtypeByVal, peraggstate->transtypeLen);
But when the copied transValue is passed to the invoke function, here is int4_avg_accum, the ArrayType returned from PG_GETARG_ARRAYTYPE_P(0) is null.
Which means the copy action is failed.
Anybody know why? Or give me some suggestions? Thanks very much.
Best Regards
Chaoyong Wang
2012/8/21 Wang, Chaoyong <Chaoyong.Wang@emc.com>: [..] > But when the copied transValue is passed to the invoke function, here is > int4_avg_accum, the ArrayType returned from PG_GETARG_ARRAYTYPE_P(0) is > null. > > Which means the copy action is failed. > > Anybody know why? Or give me some suggestions? Thanks very much. I suggest you ask this question on -hackers instead of here on -cluster-hackers, as it doesn’t seem to have anything to do with clustering. Nicolas -- A. Because it breaks the logical sequence of discussion. Q. Why is top posting bad?
Sorry, it's my mistake, I was intended to send to -hackers, but I clicked the wrong email. Anyway, I have solved the problem, thanks. -----Original Message----- From: Nicolas Barbier [mailto:nicolas.barbier@gmail.com] Sent: 2012年8月22日 17:30 To: Wang, Chaoyong Cc: pgsql-cluster-hackers@postgresql.org Subject: Re: [pgsql-cluster-hackers] How to copy Datum 2012/8/21 Wang, Chaoyong <Chaoyong.Wang@emc.com>: [..] > But when the copied transValue is passed to the invoke function, here is > int4_avg_accum, the ArrayType returned from PG_GETARG_ARRAYTYPE_P(0) is > null. > > Which means the copy action is failed. > > Anybody know why? Or give me some suggestions? Thanks very much. I suggest you ask this question on -hackers instead of here on -cluster-hackers, as it doesn’t seem to have anything to do with clustering. Nicolas -- A. Because it breaks the logical sequence of discussion. Q. Why is top posting bad?