On 3/6/2020 8:52 PM, Xinyue Chen wrote:
If I change IS NOT FALSE to IS TRUE, the results will be different.
NULL IS TRUE is always false. NULL IS NOT FALSE is always true. So it's not surprising that the results are different. SQL uses trivalent logic. NULL is neither FALSE nor TRUE.
I assume they should perform in the same way?
You assume incorrectly.
if you say "NULL IS NOT FALSE" is always true, then 'NULL IS TRUE' should also be always true.
False. -- Igor Tandetnik _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
