How to create sequence if not exists

Question

I tried to use code from Check if sequence exists in Postgres (plpgsql).

To create sequence if it does not exists. Running this code two times causes an exception:

Answer 1

I went a different route: just catch the exception:

DO
$$
BEGIN
        CREATE SEQUENCE myseq;
EXCEPTION WHEN duplicate_table THEN
        -- do nothing, it's already there
END
$$ LANGUAGE plpgsql;

One nice benefit to this is that you don't need to worry about what your current schema is.