On 7 Mar 2020, at 1:52am, Xinyue Chen <chenx...@uw.edu> wrote: > If I change IS NOT FALSE to IS TRUE, the results will be different. I > assume they should perform in the same way?
No. Because NULL is not TRUE and is not FALSE. SQLite version 3.28.0 2019-04-15 14:49:49 Enter ".help" for usage hints. Connected to a transient in-memory database. Use ".open FILENAME" to reopen on a persistent database. sqlite> SELECT NULL IS TRUE; 0 sqlite> SELECT NULL IS FALSE; 0 sqlite> SELECT NULL IS NOT TRUE; 1 sqlite> SELECT NULL IS NOT FALSE; 1 Once you can have NULL values, you have to know the rules very well when you apply logic. Other values make sense, but NULL is not logical. _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
