Обсуждение: Creating a function if it's not there in Postgres

I use a set of DDL scripts to automatically create the database for an app.

I need to create certain functions (from contrib), if they're not there already.  If they are there, I don't want to DROP or REPLACE them, since they may be used in certain indexes and triggers.

Is there a way to only CREATE a function if it is not defined already?
Is there a simple way to see if the function is defined?

(I don't want to just try creating it and letting it fail, since the DDL runs in a transaction).

Thank you.

Robert James wrote:
> I use a set of DDL scripts to automatically create the database for an app.
>
> I need to create certain functions (from contrib), if they're not there
> already.  If they are there, I don't want to DROP or REPLACE them, since
> they may be used in certain indexes and triggers.
>
> Is there a way to only CREATE a function if it is not defined already?
> Is there a simple way to see if the function is defined?
>
> (I don't want to just try creating it and letting it fail, since the DDL
> runs in a transaction).

instead of create use CREATE OR REPLACE


>
> Thank you.
>


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