> There it is again. What does length(NULL) mean ? Should it be NULL because > anything derived from "Don't know" is "Don't know" ? Or should it be a non- > negative integer representing how long the NULL value is ? I may have missed > it, but I don't think the answer is in SQL92. The only solution is not to > depend on any particular behaviour.
The result of any operation involving NULL other than IS NULL and IS NOT NULL must be NULL. Note that the coalese(x,y) is just CASE WHEN x IS NULL THEN y ELSE x END and coalesce(x,y,z) is CASE WHEN x IS NULL THEN CASE WHEN y IS NULL THEN z ELSE y END ELSE x END and so forth. --- () ascii ribbon campaign against html e-mail /\ www.asciiribbon.org _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users