Stored procedure not firing in "insert into" subquery
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Im using SQL on ORACLE 11g to insert into table1 and at the same time fire a stored procedure that inserts into table2. The stored procedure is not firing, i suspect this is because the ORACLE optimiser realises that the stored procedure is not required by the insert into table1 so it ignores it? 
Is there a way to request oracle does not optimize the query or is there a better solution.
Sample code:

INSERT INTO table1 (col1)
SELECT A.col1
FROM (SELECT col1, storedProcedure(col2)
FROM table2) A  

Any help appreciated