List stored functions that reference a table in PostgreSQL

Question

Just a quick and simple question: in PostgreSQL, how do you list the names of all stored functions/stored procedures using a table using just a SELECT statement, if possible

Answer 1

SELECT  proname, prosrc
FROM    pg_catalog.pg_namespace n
JOIN    pg_catalog.pg_proc p
ON      pronamespace = n.oid
WHERE   nspname = 'public';

Answer 2

You can use the standard information_schema schema to get metadata about your database (it's in the SQL standard, so it should work the same way in different database systems). In this case you want information_schema.routines.

Answer 3

For retrieving the argument types of the functions, which are required when referencing the function in ALTER -- using oldevectortypes worked well for me.

See How can I get a list of all functions stored in the database of a particular schema in PostgreSQL?