of untouched rows in full table scans".
SELECT ... FOR UPDATE/LOCK IN SHARE MODE statements as well as
UPDATE/DELETE statements which were executed using full table
scan were not releasing locks on rows which didn't satisfy
WHERE condition.
This bug surfaced in 5.0 and affected NDB tables. (InnoDB tables
intentionally don't support such unlocking in default mode).
This problem occured because code implementing join didn't call
handler::unlock_row() for rows which didn't satisfy part of condition
attached to this particular table/level of nested loop. So we solve
the problem adding this call.
Note that we already had this call in place in 4.1 but it was lost
(actually not quite correctly placed) when we have introduced nested
joins.
Also note that additional QA should be requested once this patch is
pushed as interaction between handler::unlock_row() and many recent
MySQL features such as subqueries, unions, views is not tested enough.
bug #18184 SELECT ... FOR UPDATE does not work..: New test case
ha_ndbcluster.h, ha_ndbcluster.cc, NdbConnection.hpp:
Fix for bug #21059 Server crashes on join query with large dataset with NDB tables: Releasing operation for each intermediate batch, before next call to trans->execute(NoCommit);
