Hi, given the following:
SELECT * FROM graph WHERE latch='bogus'; SELECT * FROM graph WHERE latch='bogus' and destid=2 and origid=1; SELECT * FROM graph WHERE latch='bogus' and origid=1; SELECT * FROM graph WHERE latch='bogus' and destid=1; SELECT * FROM graph WHERE latch='bogus' and origid=666; SELECT * FROM graph WHERE latch='bogus' and origid=NULL; A naive user would expect the same warning for all: Warning 1210 Incorrect arguments to OQGRAPH latch However, the following two cases produce no warning: SELECT * FROM graph WHERE latch='bogus'; SELECT * FROM graph WHERE latch='bogus' and origid=NULL; At a guess I suspect the second is caused because the clause `and origid=NULL` is evaluated first, and there being no rows having origid=NULL, the RDBMS optimises away the call into our code. But why would the first produce no warning? If it was a case of the optimiser saying "There is no AND clause therefore produce all rows in the backing store" should it not still hit our storage engine? --Andrew -- Mailing list: https://launchpad.net/~oqgraph-dev Post to : oqgraph-dev@lists.launchpad.net Unsubscribe : https://launchpad.net/~oqgraph-dev More help : https://help.launchpad.net/ListHelp
