How to delete or change DB/2 SQL Stored Procedures with duplicate/same name.

Using DB/2 for IBM i (aka IBM AS/400 or iSeries) I was trying to drop a stored procedure using the command

DROP PROCEDURE TEST/TEST_FTP;

But was getting a message

Message: [SQL0476] Routine TEST_FTP in TEST not unique. Cause . . . . . : Function or procedure TEST_FTP in TEST was specified, not by signature or specific name, and more than one specific instance of the routine was found. Or the procedure was used in a DESCRIBE PROCEDURE or ASSOCIATE LOCATOR statement without a schema name specified while connected to a remote system, and more than one procedure has been called with that name. Recovery . . . : Request the routine either by its specific name, or by its signature (function or procedure name with parameter types). If this is for a DESCRIBE PROCEDURE or ASSOCIATE LOCATOR statement, specify the schema name for the procedure. Try the request again.

Using Ops Navigator, to view the stored procedures I was getting an idex array error message, if I used query to query SYSRoutine in QSYS2, I could see 2 entries for this with slightly different settings in the SPECIFIC_NAME, but the ROUTINE_NAME was the same as TEST_FTP.

After some investigation I found that you could drop and specify the parameters, so I tried

DROP PROCEDURE TEST/TEST_FTP(CHAR(13));

Which successfully make the name unique and allow me to delete one, then managed to call

DROP PROCEDURE TEST/TEST_FTP;

Which then deleted the other one of the same name.

Basically in DB/2 on IBM i and I guess most other SQL databases stored procedures can have the same name as long as they have different parameters. This is essentially the same as method overloading in Java and some other languages where the method (sub routine) names signature is composed of the name part + the parameter list that is passed into it.