"soni de" <soni(dot)de(at)gmail(dot)com> writes:
> I am getting following error while inserting a row into the "abc" table:
> *ERROR: fmgr_info: function 2720768: cache lookup failed*
What PG version is this? (I can tell from the spelling of the error
message that it's older than 7.4.) If it's pre-7.3 then the answer is
probably that you dropped and re-created the function, and now need to
drop and re-create the trigger to match. 7.3 shouldn't have let you
drop a function that has a trigger depending on it, though.
BTW this seems a bit off-topic for pgsql-performance.
regards, tom lane