Create or Update Function

I've got a script to update the schema on a number of servers. These
servers are at various versions of the schema, so I used the following
syntax for each function, not knowing if it needed to be created or merely
updated:

CREATE OR REPLACE FUNCTION foo() .

But I get the error, "function foo() does not exist" if it indeed does not
exist. Shouldn't the "create or replace" just create it in this instance?
Why the error?

Thanks,

Steve Erickson

Senior Developer

266 East 7th Street, Floor 4

Saint Paul, MN 55101

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