Heikki Linnakangas <heikki@enterprisedb.com> writes:
> Tom Lane wrote:
>> If we go this route it seems like we'll need four more columns in
>> pg_proc (cost estimation function OID, rowcount estimation function OID,
>> fallback cost constant, fallback rowcount constant).
> What would the fallbacks be for?
By "fallback" I meant "this is what to use if no estimation function is
provided".
I'm envisioning that the CREATE FUNCTION syntax would add optional
clauses
COST function-name-or-numeric-constant ROWS function-name-or-numeric-constant
that would be used to fill these columns.
regards, tom lane