• Sujatha's avatar
    MDEV-11094: Blackhole table updates on slave fail when row annotation is enabled · b3473961
    Sujatha authored
    Problem:
    =======
    rpl_blackhole.test fails when executed with following options
    mysqld=--binlog_annotate_row_events=1, mysqld=--replicate_annotate_row_events=1
    
    Test output:
    ------------
    worker[1] Using MTR_BUILD_THREAD 300, with reserved ports 16000..16019
    rpl.rpl_blackhole_bug 'mix'              [ pass ]    791
    rpl.rpl_blackhole_bug 'row'              [ fail ]
    Replicate_Wild_Ignore_Table
    Last_Errno	1032
    Last_Error	Could not execute Update_rows_v1 event on table test.t1; Can't find
    record in 't1', Error_code: 1032; handler error HA_ERR_END_OF_FILE; the event's
    master log master-bin.000001, end_log_pos 1510
    
    Analysis:
    =========
    Enabling "replicate_annotate_row_events" on slave, Tells the slave to write
    annotate rows events received from the master to its own binary log. The
    received annotate events are applied after the Gtid event as shown below.
    thd->query() will be set to the actual query received from the master, through
    annotate event. Annotate_rows event should not be deleted after the event is
    applied as the thd->query will be used to generate new Annotate_rows event
    during applying the subsequent Rows events. After the last Rows event has been
    applied, the saved Annotate_rows event (if any) will be deleted.
    
    In balckhole engine all the DML operations are noops as they donot store any
    data. They simply return success without doing any operation. But the existing
    strictly expects thd->query() to be 'NULL' to identify that row based
    replication is in use. This assumption will fail when row annotations are
    enabled as the query is not 'NULL'. Hence various row based operations like
    'update', 'delete', 'index lookup' will fail when row annotations are enabled.
    
    Fix:
    ===
    Extend the row based replication check to include row annotations as well.
    i.e Either the thd->query() is NULL or thd->query() points to query and row
    annotations are in use.
    b3473961
rpl_blackhole_row_annotate-slave.opt 61 Bytes