Re: select sql slow inside function

On 09/15/2010 09:46 AM, Gary Fu wrote:
> On 09/15/2010 02:28 AM, Sergey Konoplev wrote:
>> Hi,
>>
>> On 15 September 2010 01:56, Gary Fu<gfu(at)sigmaspace(dot)com> wrote
>>> I have a function proc_TaskComplete that inserts a record to table
>>> TaskHistory and then calls another function proc_ExportTaskComplete,
>>> that
>>> will retrieve (select) the record just inserted based on an index column
>>> (TaskId) in that table TaskHistory. I noticed that the select sql
>>> (inside
>>> proc_ExportTaskComplete) will take 3 seconds. Under normal condition
>>> (psql)
>>> the select sql is fast enough with the index. Can anyone explain why
>>> and how
>>> to fix the problem ?
>>> My postgresql version is 8.4.4
>>
>> Could you please provide a use-case?
>>
>>
>>>
>>> Thanks,
>>> Gary
>>>
>>> --
>>>
> We found out the problem and it was caused by the type used in the 2nd
> function for the key column (argument passed in from the main function)
> is numerical (12) instead of T_TaskId type, even though the T_TaskId is
> defined as 'numerical(12), 'not null'.
>
> Thanks,
> Gary

Sorry, I made mistake again, the T_TaskId is Integer, not Numerical(12)
and I think due to the type difference, the table scan, instead of the
index is used.

Thanks,
Gary