Mysql if exists drop function doesn't work with code 1305

Question

When I try to execute the code below, I get mysql error 1305:

 DROP FUNCTION IF EXISTS myFunction; 

It does not work when the function does not exist. But why? Isn't that a cleaning step before re-creating functions?

Answer 1

MySQL error # 33813 explains that this may be due to case sensitivity:

Since MySQL 5.0.52 DROP FUNCTION commands containing function names with schema qualifications compare the schema name with case sensitivity even when lower_case_table_names is set to 1. This means that the functions are not defined correctly.