Thread: Re: Altering a plan

Re: Altering a plan

From
"Shruthi A"
Date:

Hi,

I want to take a plan generated by the postgres optimizer and insert a constant in place of another constant in the plan. There is a function OidOutputFunctionCall( ) to get the constant. Similarly, is there any function to set the value of the constant?   Also what does OidInputFunctionCall( ) do?

Please reply soon, this is an emergency..

Thanks a lot,
Shruthi



Re: Altering a plan

From
Warren Turkal
Date:
On Monday 16 July 2007 22:32:07 Shruthi A wrote:
> > > Please reply soon, this is an emergency..

This may be obvious, but a quick reply might call for commercial support. 
Check out [1].

[1]http://www.postgresql.org/support/professional_support

wt
-- 
Warren Turkal (w00t)


Re: Altering a plan

From
Heikki Linnakangas
Date:
Shruthi A wrote:
>> > I want to take a plan generated by the postgres optimizer and insert a
>> > constant in place of another constant in the plan. There is a function
>> > OidOutputFunctionCall( ) to get the constant. Similarly, is there any
>> > function to set the value of the constant?   Also what does
>> > OidInputFunctionCall( ) do?

Why?

--  Heikki Linnakangas EnterpriseDB   http://www.enterprisedb.com


Re: Altering a plan

From
Heikki Linnakangas
Date:
Please keep the list cc'd.

Shruthi A wrote:
> On 7/17/07, Heikki Linnakangas <heikki@enterprisedb.com> wrote:
>> Shruthi A wrote:
>> >> > I want to take a plan generated by the postgres optimizer and insert
>> a
>> >> > constant in place of another constant in the plan. There is a
>> function
>> >> > OidOutputFunctionCall( ) to get the constant. Similarly, is there
>> any
>> >> > function to set the value of the constant?   Also what does
>> >> > OidInputFunctionCall( ) do?
>>
>> Why?
>>
> Actually i'm trying to write a function where the plan which is optimal for
> one query is enforced for another query (and the 2 queries differ only in a
> constant value of a predicate).

How about using a parameter instead of a constant?

--  Heikki Linnakangas EnterpriseDB   http://www.enterprisedb.com