Result set ordering

SQE implementation may result in a different result set ordering for WRKQRY, RUNQRY, or OPNQRYF.

When a query is performed without explicitly specifying that the results be returned in a specific order, both the SQE and CQE optimizers will choose whatever plan will perform the best. This means that both SQE and CQE may or may not return the results in a keyed file order. Since CQE has far less advanced capability than SQE, it is more likely to return the results in a keyed order and SQE is less likely to return the results in a keyed order. Hence, if a query is specified with WRKQRY, RUNQRY, or OPNQRYF and the row ordering is important, explicitly specify the key field(s) and key field ordering.