Create A Temp Table (if Not Exists) For Use Into A Custom Procedure

Answer :

DROP Table each time before creating TEMP table as below:

BEGIN
  DROP TABLE IF EXISTS temp_table1;
  create temp table temp_table1
  -- Your rest Code comes here

The problem of temp tables is that dropping and recreating temp table bloats pg_attribute heavily and therefore one sunny morning you will find db performance dead, and pg_attribute 200+ gb while your db would be like 10gb.

So we're very heavy on temp tables having >500 rps and async i\o via nodejs and thus experienced a very heavy bloating of pg_attribute because of that. All you are left with is a very aggressive vacuuming which halts performance.
All answers given here do not solve this, because they all bloat pg_attribute heavily.

So the solution is elegantly this

create temp table if not exists my_temp_table (description) on commit delete rows;

So you go on playing with temp tables and save your pg_attribute.

You want to DROP term table after commit (not DELETE ROWS), so:

begin
  create temp table temp_table1
  on commit drop
...

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