Bug#54201: "SET INSERT_ID" event must be ignored if corresponding event is ignored

An INSERT query log event is preceeded by an INSERT_ID intvar event if the
INSERT allocates a new auto_increment value. But if we ignore the INSERT
due to --replicate-ignore-table or similar, then the INSERT_ID event is
still executed, and the set value of INSERT_ID lingers around in the
slave sql thread THD object indefinitely until the next INSERT that
happens to need allocation of a new auto_increment value.

Normally this does not cause problems as such following INSERT would
normally come with its own INSERT_ID event. In this bug, the user had
a trigger on the slave which was missing on the master, and this
trigger had an INSERT which could be affected. In any case, it seems
better to not leave a stray INSERT_ID hanging around in the sql thread
THD indefinitely.

Note that events can also be skipped from apply_event_and_update_pos();
however it is not possible in that code to skip the INSERT without also
skipping the INSERT_ID event.

1 files changed, 13 insertions, 0 deletions

diff --git a/sql/log_event.cc b/sql/log_event.cc
index 3969b6b6f4d..c3e5a831ab3 100644
--- a/sql/log_event.cc
+++ b/sql/log_event.cc
@@ -3307,6 +3307,19 @@ START SLAVE; . Query: '%s'", expected_error, thd->query());
     /* If the query was not ignored, it is printed to the general log */
     if (!thd->is_error() || thd->main_da.sql_errno() != ER_SLAVE_IGNORED_TABLE)
       general_log_write(thd, COM_QUERY, thd->query(), thd->query_length());
+    else
+    {
+      /*
+        Bug#54201: If we skip an INSERT query that uses auto_increment, then we
+        should reset any @@INSERT_ID set by an Intvar_log_event associated with
+        the query; otherwise the @@INSERT_ID will linger until the next INSERT
+        that uses auto_increment and may affect extra triggers on the slave etc.
+
+        We reset INSERT_ID unconditionally; it is probably cheaper than
+        checking if it is necessary.
+      */
+      thd->auto_inc_intervals_forced.empty();
+    }
 
 compare_errors: