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A:The Call DB Procedure needs to be triggered. Use a Row generator step generating e.g. 1 empty row and link that with a hop to the Call DB Procedure step.
Which permissions are required for MySQL 5.X?
Before PDI executes the stored procedure named in the Proc-name field, it first submits a SHOW CREATE PROCEDURE. This will fail, and cause PDI to report a Null Pointer Exception, unless permission has been granted. Of course, the user must also have permission to execute the procedure. Example statements for granting the needed permissions are:
grant select on mysql.proc to U;
grant execute on procedure P to U;