diff options
Diffstat (limited to 'sql/handler.cc')
-rw-r--r-- | sql/handler.cc | 25 |
1 files changed, 22 insertions, 3 deletions
diff --git a/sql/handler.cc b/sql/handler.cc index ee02441e7ff..c0a5e2ff55c 100644 --- a/sql/handler.cc +++ b/sql/handler.cc @@ -1245,7 +1245,14 @@ end: /** @note This function does not care about global read lock. A caller should. + + @param[in] all Is set in case of explicit commit + (COMMIT statement), or implicit commit + issued by DDL. Is not set when called + at the end of statement, even if + autocommit=1. */ + int ha_commit_one_phase(THD *thd, bool all) { int error=0; @@ -1253,9 +1260,15 @@ int ha_commit_one_phase(THD *thd, bool all) /* "real" is a nick name for a transaction for which a commit will make persistent changes. E.g. a 'stmt' transaction inside a 'all' - transation is not 'real': even though it's possible to commit it, + transaction is not 'real': even though it's possible to commit it, the changes are not durable as they might be rolled back if the enclosing 'all' transaction is rolled back. + We establish the value of 'is_real_trans' by checking + if it's an explicit COMMIT/BEGIN statement, or implicit + commit issued by DDL (all == TRUE), or if we're running + in autocommit mode (it's only in the autocommit mode + ha_commit_one_phase() can be called with an empty + transaction.all.ha_list, see why in trans_register_ha()). */ bool is_real_trans=all || thd->transaction.all.ha_list == 0; Ha_trx_info *ha_info= trans->ha_list, *ha_info_next; @@ -1303,9 +1316,15 @@ int ha_rollback_trans(THD *thd, bool all) /* "real" is a nick name for a transaction for which a commit will make persistent changes. E.g. a 'stmt' transaction inside a 'all' - transation is not 'real': even though it's possible to commit it, + transaction is not 'real': even though it's possible to commit it, the changes are not durable as they might be rolled back if the enclosing 'all' transaction is rolled back. + We establish the value of 'is_real_trans' by checking + if it's an explicit COMMIT or BEGIN statement, or implicit + commit issued by DDL (in these cases all == TRUE), + or if we're running in autocommit mode (it's only in the autocommit mode + ha_commit_one_phase() is called with an empty + transaction.all.ha_list, see why in trans_register_ha()). */ bool is_real_trans=all || thd->transaction.all.ha_list == 0; DBUG_ENTER("ha_rollback_trans"); @@ -1358,7 +1377,7 @@ int ha_rollback_trans(THD *thd, bool all) if (all) thd->variables.tx_isolation=thd->session_tx_isolation; } - /* Always cleanup. Even if there nht==0. There may be savepoints. */ + /* Always cleanup. Even if nht==0. There may be savepoints. */ if (is_real_trans) thd->transaction.cleanup(); if (all) |