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Negative conditions in WHERE clause (but not over indexed fields)
I have just done a small report with your select and tested in SE30, the selection without <> in where clause took 9.328 microsec. With '<>' operator the program took 51.086 microsec.
As you can see in the link above, if you use the table index in the selection, use the '<>' operator in a non-index field could help the selection, otherwise better not to use.
Regards,
Felipe
Message was edited by: Felipe Simionatto