Carefully removing? You mean press "enter" gently after typing DROP INDEX? err, no.
The thinking is that it takes a long time to build an index, and a short time to drop one. What we want is a way of removing the index that if we discover that removing it was a mistake, we can put the index back again quickly.
First, create the following function:
CREATE OR REPLACE FUNCTION trial_drop_index(iname TEXT) RETURNS VOID LANGUAGE SQL AS $$ UPDATE pg_index SET indisvalid = false WHERE indexrelid = $1::regclass; $$;
then, run it to do a trial of dropping the index.
If you experience performance issues after dropping the index, then use the following function to "undrop" the index:
CREATE OR REPLACE FUNCTION ...