[sqlite] Trigger, syntax question

[Wolfgang Meiners]

Hi,

I have written the following trigger with ideas from stackoverflow:

(OSX 10.6.8, SQLite 3.6.12)

This is for a book library. If i delete a bookexemplar from the library,
this should not be possible if this bookexemplar is on loan, which means
ausleihen.rueckgabe IS NULL. Otherwise every information on loans should
be deleted, too.

CREATE TRIGGER buchexemplare_delete
        AFTER DELETE ON buchexemplare
        FOR EACH ROW
        BEGIN
            SELECT CASE
            WHEN EXISTS (SELECT beid FROM ausleihen
                   WHERE (ausleihen.beid = OLD.beid) AND\
                         (ausleihen.rueckgabe IS NULL))
            THEN RAISE(ROLLBACK, 'Es sind noch Buchexemplare\
                                  ausgeliehen')
            END;
            DELETE FROM ausleihen
            WHERE ausleihen.beid = OLD.beid;
        END;

this trigger does work but i think it is not in accordance with the
syntax diagram of TRIGGER on
http://sqlite.com/lang_createtrigger.html

So where can i find the exact actual syntax for triggers and maybe some
examples?

Thank you for any help
Wolfgang

_______________________________________________
sqlite-users mailing list
sqlite-users@sqlite.org
http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users