Question

My boss sent me a process, in to which I need to:

• make a function that creates a temp table
• grab data from a table
• use a function to refine the data
• create a hash code for 2 of the columns
• insert all the data from the temp to the original data
• drop the table

I’ve been trying to look what the make_hash() function does. Whenever I run the FUNCTION it gives me an error on that line, so I’m guessing I need to declare it first before the begin statement in the create function. Or is it a user-created function? If so, is there a way for me to find which schema the function is located?

I’ve been trying to research in the books and online but I couldn’t find anything, even in the PostgreSQL website.

--------------------------------------------

ERROR:  function make_hash(character varying) does not exist
LINE 1: UPDATE temp_match_queue_04022012 SET title_hash = make_hash(...
                                                          ^
HINT:  No function matches the given name and argument types. You might need to add explicit type casts.
QUERY:  UPDATE temp_match_queue_04022012 SET title_hash = make_hash(as_title) WHERE as_title IS NOT NULL
CONTEXT:  PL/pgSQL function "metadata_matching_temp" line 30 at SQL statement

********** Error **********

ERROR: function make_hash(character varying) does not exist
SQL state: 42883
Hint: No function matches the given name and argument types. You might need to add explicit type casts.
Context: PL/pgSQL function "metadata_matching_temp" line 30 at SQL statement

Answer 1

As @Clodoaldo mentioned look into pgcrypto (which you would get by installing it to your postgres, on debian its in postgresql-contrib iirc).

Any function you call must be available before the BEGIN section. You can combine functions into packages if you need more than one.