The problem was that TRUNCATE TABLE didn't take a exclusive
lock on a table if it resorted to truncating via delete of
all rows in the table. Specifically for InnoDB tables, this
could break proper isolation as InnoDB ends up aborting some
granted locks when truncating a table.
The solution is to take a exclusive metadata lock before
TRUNCATE TABLE can proceed. This guarantees that no other
transaction is using the table.
Incompatible change: Truncate via delete no longer fails
if sql_safe_updates is activated (this was a undocumented
side effect).
TRUNCATE TABLE fails to replicate when stmt-based binlogging is not supported.
Correcting some tests that was failing in pushbuild as well as fixing result
file for some tests that are not executed in the default MTR run.
TRUNCATE TABLE fails to replicate when stmt-based binlogging is not supported.
There were two separate problems with the code, both of which are fixed with
this patch:
1. An error was printed by InnoDB for TRUNCATE TABLE in statement mode when
the in isolation levels READ COMMITTED and READ UNCOMMITTED since InnoDB
does permit statement-based replication for DML statements. However,
the TRUNCATE TABLE is not transactional, but is a DDL, and should therefore
be allowed to be replicated as a statement.
2. The statement was not logged in mixed mode because of the error above, but
the error was not reported to the client.
This patch fixes the problem by treating TRUNCATE TABLE a DDL, that is, it is
always logged as a statement and not reporting an error from InnoDB for TRUNCATE
TABLE.
