Universal SQL procedure

Hi guys.
I hope anyone can help me.

I need an "universal sql procedure" (RPGIV)
The only parameter is the sql-statement
The result of the sql-procedure should be the whole record of the sql or only the
fields that i have selected in the sql-statement.

       
Until now we solved the problem on this way.
We have a sql_procedure with 2 parms.

For Example:
callp   sql_exec('FILENAME':SQL_STATEMENT)

In the procedure we have a select-statement on the filename.
For every file we have DECLARE, PREPARE, ...... statements and
export-data-structures.

The problem:   
For every new file in the sql-procedure we need a
new cursor/declare/prepare statement and the
export-data-strcuture declaration.

For Example:
d file1_ds      e ds                  extname(file1)  
d file2_ds      e ds                  extname(file2)
d file3_ds      e ds                  extname(file3)  

How can i make this universal ? With only one cursor declaration and
one global Export-DS ?

Stefan