<div id="docs-body">
 <div class="section">
  <div class="titlepage">
   <div>
    <div>
     <h4 class="title">
      <a name="replica-logs-status">
      </a>
      19.2.4.2 Replication Metadata Repositories
     </h4>
    </div>
   </div>
  </div>
  <p>
   A replica server creates two replication metadata repositories,
        the connection metadata repository and the applier metadata
        repository. The replication metadata repositories survive a
        replica server's shutdown. If binary log file position
        based replication is in use, when the replica restarts, it reads
        the two repositories to determine how far it previously
        proceeded in reading the binary log from the source and in
        processing its own relay log. If GTID-based replication is in
        use, the replica does not use the replication metadata
        repositories for that purpose, but does need them for the other
        metadata that they contain.
  </p>
  <div class="itemizedlist">
   <ul class="itemizedlist" style="list-style-type: disc; ">
    <li class="listitem">
     <p>
      The replica's
      <span class="emphasis">
       <em>
        connection metadata
            repository
       </em>
      </span>
      contains information that the
            replication I/O (receiver) thread needs to connect to the
            replication source server and retrieve transactions from the
            source's binary log. The metadata in this repository
            includes the connection configuration, the replication user
            account details, the SSL settings for the connection, and
            the file name and position where the replication receiver
            thread is currently reading from the source's binary log.
     </p>
    </li>
    <li class="listitem">
     <p>
      The replica's
      <span class="emphasis">
       <em>
        applier metadata
            repository
       </em>
      </span>
      contains information that the
            replication SQL (applier) thread needs to read and apply
            transactions from the replica's relay log. The metadata in
            this repository includes the file name and position up to
            which the replication applier thread has executed the
            transactions in the relay log, and the equivalent position
            in the source's binary log. It also includes metadata for
            the process of applying transactions, such as the number of
            worker threads and the
      <code class="literal">
       PRIVILEGE_CHECKS_USER
      </code>
      account for the
            channel.
     </p>
    </li>
   </ul>
  </div>
  <p>
   The connection metadata repository is written to the
   <code class="literal">
    slave_master_info
   </code>
   table in the
   <code class="literal">
    mysql
   </code>
   system schema, and the applier metadata
        repository is written to the
   <code class="literal">
    slave_relay_log_info
   </code>
   table in the
   <code class="literal">
    mysql
   </code>
   system schema. A warning message is
        issued if
   <a class="link" href="mysqld.html" title="6.3.1 mysqld — The MySQL Server">
    <span class="command">
     <strong>
      mysqld
     </strong>
    </span>
   </a>
   is unable to initialize the
        tables for the replication metadata repositories, but the
        replica is allowed to continue starting. This situation is most
        likely to occur when upgrading from a version of MySQL that does
        not support the use of tables for the repositories to one in
        which they are supported.
  </p>
  <div class="important" style="margin-left: 0.5in; margin-right: 0.5in;">
   <div class="admon-title">
    Important
   </div>
   <div class="orderedlist">
    <ol class="orderedlist" type="1">
     <li class="listitem">
      <p>
       Do not attempt to update or insert rows in the
       <code class="literal">
        mysql.slave_master_info
       </code>
       or
       <code class="literal">
        mysql.slave_relay_log_info
       </code>
       tables
              manually. Doing so can cause undefined behavior, and is
              not supported. Execution of any statement requiring a
              write lock on either or both of the
       <code class="literal">
        slave_master_info
       </code>
       and
       <code class="literal">
        slave_relay_log_info
       </code>
       tables is
              disallowed while replication is ongoing (although
              statements that perform only reads are permitted at any
              time).
      </p>
     </li>
     <li class="listitem">
      <p>
       Access privileges for the connection metadata repository
              table
       <code class="literal">
        mysql.slave_master_info
       </code>
       should be
              restricted to the database administrator, because it
              contains the replication user account name and password
              for connecting to the source. Use a restricted access mode
              to protect database backups that include this table. You
              can clear the replication user account credentials from
              the connection metadata repository, and instead always
              provide them using a
       <a class="link" href="start-replica.html" title="15.4.2.4 START REPLICA Statement">
        <code class="literal">
         START
              REPLICA
        </code>
       </a>
       statement to start the replication
              channel. This approach means that the replication channel
              always needs operator intervention to restart, but the
              account name and password are not recorded in the
              replication metadata repositories.
      </p>
     </li>
    </ol>
   </div>
  </div>
  <p>
   <a class="link" href="reset-replica.html" title="15.4.2.3 RESET REPLICA Statement">
    <code class="literal">
     RESET REPLICA
    </code>
   </a>
   clears the data in
        the replication metadata repositories, with the exception of the
        replication connection parameters (depending on the MySQL Server
        release). For details, see the description for
   <a class="link" href="reset-replica.html" title="15.4.2.3 RESET REPLICA Statement">
    <code class="literal">
     RESET REPLICA
    </code>
   </a>
   .
  </p>
  <p>
   You can set the
   <code class="literal">
    GTID_ONLY
   </code>
   option of the
   <a class="link" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
    <code class="literal">
     CHANGE REPLICATION SOURCE TO
    </code>
   </a>
   statement to stop a replication channel from persisting file
        names and file positions in the replication metadata
        repositories. This avoids writes and reads to the tables in
        situations where GTID-based replication does not actually
        require them. With the
   <code class="literal">
    GTID_ONLY
   </code>
   setting, the
        connection metadata repository and the applier metadata
        repository are not updated when the replica queues and applies
        events in a transaction, or when the replication threads are
        stopped and started. File positions are tracked in memory, and
        can be viewed using
   <a class="link" href="show-replica-status.html" title="15.7.7.35 SHOW REPLICA STATUS Statement">
    <code class="literal">
     SHOW REPLICA
        STATUS
    </code>
   </a>
   if they are needed. The replication metadata
        repositories are only synchronized in the following situations:
  </p>
  <div class="itemizedlist">
   <ul class="itemizedlist" style="list-style-type: disc; ">
    <li class="listitem">
     <p>
      When a
      <a class="link" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
       <code class="literal">
        CHANGE REPLICATION SOURCE
            TO
       </code>
      </a>
      statement is issued.
     </p>
    </li>
    <li class="listitem">
     <p>
      When a
      <a class="link" href="reset-replica.html" title="15.4.2.3 RESET REPLICA Statement">
       <code class="literal">
        RESET REPLICA
       </code>
      </a>
      statement is issued.
      <code class="literal">
       RESET REPLICA ALL
      </code>
      deletes rather than updates the repositories, so they are
            synchronized implicitly.
     </p>
    </li>
    <li class="listitem">
     <p>
      When a replication channel is initialized.
     </p>
    </li>
    <li class="listitem">
     <p>
      If the replication metadata repositories are moved from
            files to tables.
     </p>
    </li>
   </ul>
  </div>
  <p>
   Creating the replication metadata repositories as tables is the
        default; the use of files is deprecated.
  </p>
  <p>
   The
   <code class="literal">
    mysql.slave_master_info
   </code>
   and
   <code class="literal">
    mysql.slave_relay_log_info
   </code>
   tables are created
        using the
   <a class="link" href="innodb-storage-engine.html" title="Chapter 17 The InnoDB Storage Engine">
    <code class="literal">
     InnoDB
    </code>
   </a>
   transactional
        storage engine. Updates to the applier metadata repository table
        are committed together with the transactions, meaning that the
        replica's progress information recorded in that repository is
        always consistent with what has been applied to the database,
        even in the event of an unexpected server halt. For information
        on the combination of settings on a replica that is most
        resilient to unexpected halts, see
   <a class="xref" href="replication-solutions-unexpected-replica-halt.html" title="19.4.2 Handling an Unexpected Halt of a Replica">
    Section 19.4.2, “Handling an Unexpected Halt of a Replica”
   </a>
   .
  </p>
  <p>
   When you back up the replica's data or transfer a snapshot of
        its data to create a new replica, ensure that you include the
   <code class="literal">
    mysql.slave_master_info
   </code>
   and
   <code class="literal">
    mysql.slave_relay_log_info
   </code>
   tables containing
        the replication metadata repositories. For cloning operations,
        note that when the replication metadata repositories are created
        as tables, they are copied to the recipient during a cloning
        operation, but when they are created as files, they are not
        copied. When binary log file position based replication is in
        use, the replication metadata repositories are needed to resume
        replication after restarting the restored, copied, or cloned
        replica. If you do not have the relay log files, but still have
        the applier metadata repository, you can check it to determine
        how far the replication SQL thread has executed in the source's
        binary log. Then you can use a
   <a class="link" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
    <code class="literal">
     CHANGE
        REPLICATION SOURCE TO
    </code>
   </a>
   statement with the
   <code class="literal">
    SOURCE_LOG_FILE
   </code>
   and
   <code class="literal">
    SOURCE_LOG_POS
   </code>
   options to tell the replica to
        re-read the binary logs from the source from that point
        (provided that the required binary logs still exist on the
        source).
  </p>
  <p>
   One additional repository, the applier worker metadata
        repository, is created primarily for internal use, and holds
        status information about worker threads on a multithreaded
        replica. The applier worker metadata repository includes the
        names and positions for the relay log file and the source's
        binary log file for each worker thread. If the applier metadata
        repository is created as a table, which is the default, the
        applier worker metadata repository is written to the
   <code class="literal">
    mysql.slave_worker_info
   </code>
   table. If the applier
        metadata repository is written to a file, the applier worker
        metadata repository is written to the
   <code class="filename">
    worker-relay-log.info
   </code>
   file. For external
        use, status information for worker threads is presented in the
        Performance Schema
   <a class="link" href="performance-schema-replication-applier-status-by-worker-table.html" title="29.12.11.7 The replication_applier_status_by_worker Table">
    <code class="literal">
     replication_applier_status_by_worker
    </code>
   </a>
   table.
  </p>
  <p>
   The replication metadata repositories originally contained
        information similar to that shown in the output of the
   <a class="link" href="show-replica-status.html" title="15.7.7.35 SHOW REPLICA STATUS Statement">
    <code class="literal">
     SHOW REPLICA STATUS
    </code>
   </a>
   statement,
        which is discussed in
   <a class="xref" href="replication-statements-replica.html" title="15.4.2 SQL Statements for Controlling Replica Servers">
    Section 15.4.2, “SQL Statements for Controlling Replica Servers”
   </a>
   . Further
        information has since been added to the replication metadata
        repositories which is not displayed by the
   <a class="link" href="show-replica-status.html" title="15.7.7.35 SHOW REPLICA STATUS Statement">
    <code class="literal">
     SHOW REPLICA STATUS
    </code>
   </a>
   statement.
  </p>
  <p>
   For the connection metadata repository, the following table
        shows the correspondence between the columns in the
   <code class="literal">
    mysql.slave_master_info
   </code>
   table, the columns
        displayed by
   <a class="link" href="show-replica-status.html" title="15.7.7.35 SHOW REPLICA STATUS Statement">
    <code class="literal">
     SHOW REPLICA STATUS
    </code>
   </a>
   ,
        and the lines in the deprecated
   <code class="filename">
    master.info
   </code>
   file.
  </p>
  <div class="informaltable">
   <table summary="The correspondence between the columns in the mysql.slave_master_info table, the columns displayed by SHOW REPLICA STATUS, and the lines in the deprecated master.info file.">
    <colgroup>
     <col style="width: 31%"/>
     <col style="width: 40%"/>
     <col style="width: 16%"/>
     <col style="width: 18%"/>
    </colgroup>
    <thead>
     <tr>
      <th scope="col">
       <code class="literal">
        slave_master_info
       </code>
       Table Column
      </th>
      <th scope="col">
       <code class="literal">
        SHOW REPLICA STATUS
       </code>
       Column
      </th>
      <th scope="col">
       <code class="filename">
        master.info
       </code>
       File Line
      </th>
      <th scope="col">
       Description
      </th>
     </tr>
    </thead>
    <tbody>
     <tr>
      <th scope="row">
       <code class="literal">
        Number_of_lines
       </code>
      </th>
      <td>
       [None]
      </td>
      <td>
       1
      </td>
      <td>
       Number of columns in the table (or lines in the file)
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Master_log_name
       </code>
      </th>
      <td>
       <code class="literal">
        Source_Log_File
       </code>
      </td>
      <td>
       2
      </td>
      <td>
       The name of the binary log currently being read from the source
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Master_log_pos
       </code>
      </th>
      <td>
       <code class="literal">
        Read_Source_Log_Pos
       </code>
      </td>
      <td>
       3
      </td>
      <td>
       The current position within the binary log that has been read from the
              source
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Host
       </code>
      </th>
      <td>
       <code class="literal">
        Source_Host
       </code>
      </td>
      <td>
       4
      </td>
      <td>
       The host name of the replication source server
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        User_name
       </code>
      </th>
      <td>
       <code class="literal">
        Source_User
       </code>
      </td>
      <td>
       5
      </td>
      <td>
       The replication user account name used to connect to the source
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        User_password
       </code>
      </th>
      <td>
       Password (not shown by
       <a class="link" href="show-replica-status.html" title="15.7.7.35 SHOW REPLICA STATUS Statement">
        <code class="literal">
         SHOW REPLICA
              STATUS
        </code>
       </a>
       )
      </td>
      <td>
       6
      </td>
      <td>
       The replication user account password used to connect to the source
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Port
       </code>
      </th>
      <td>
       <code class="literal">
        Source_Port
       </code>
      </td>
      <td>
       7
      </td>
      <td>
       The network port used to connect to the replication source server
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Connect_retry
       </code>
      </th>
      <td>
       <code class="literal">
        Connect_Retry
       </code>
      </td>
      <td>
       8
      </td>
      <td>
       The period (in seconds) that the replica waits before trying to
              reconnect to the source
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Enabled_ssl
       </code>
      </th>
      <td>
       <code class="literal">
        Source_SSL_Allowed
       </code>
      </td>
      <td>
       9
      </td>
      <td>
       Whether the replica supports SSL connections
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Ssl_ca
       </code>
      </th>
      <td>
       <code class="literal">
        Source_SSL_CA_File
       </code>
      </td>
      <td>
       10
      </td>
      <td>
       The file used for the Certificate Authority (CA) certificate
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Ssl_capath
       </code>
      </th>
      <td>
       <code class="literal">
        Source_SSL_CA_Path
       </code>
      </td>
      <td>
       11
      </td>
      <td>
       The path to the Certificate Authority (CA) certificate
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Ssl_cert
       </code>
      </th>
      <td>
       <code class="literal">
        Source_SSL_Cert
       </code>
      </td>
      <td>
       12
      </td>
      <td>
       The name of the SSL certificate file
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Ssl_cipher
       </code>
      </th>
      <td>
       <code class="literal">
        Source_SSL_Cipher
       </code>
      </td>
      <td>
       13
      </td>
      <td>
       The list of possible ciphers used in the handshake for the SSL
              connection
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Ssl_key
       </code>
      </th>
      <td>
       <code class="literal">
        Source_SSL_Key
       </code>
      </td>
      <td>
       14
      </td>
      <td>
       The name of the SSL key file
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Ssl_verify_server_cert
       </code>
      </th>
      <td>
       <code class="literal">
        Source_SSL_Verify_Server_Cert
       </code>
      </td>
      <td>
       15
      </td>
      <td>
       Whether to verify the server certificate
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Heartbeat
       </code>
      </th>
      <td>
       [None]
      </td>
      <td>
       16
      </td>
      <td>
       Interval between replication heartbeats, in seconds
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Bind
       </code>
      </th>
      <td>
       <code class="literal">
        Source_Bind
       </code>
      </td>
      <td>
       17
      </td>
      <td>
       Which of the replica's network interfaces should be used for
              connecting to the source
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Ignored_server_ids
       </code>
      </th>
      <td>
       <code class="literal">
        Replicate_Ignore_Server_Ids
       </code>
      </td>
      <td>
       18
      </td>
      <td>
       The list of server IDs to be ignored. Note that for
       <code class="literal">
        Ignored_server_ids
       </code>
       the list of server
              IDs is preceded by the total number of server IDs to
              ignore.
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Uuid
       </code>
      </th>
      <td>
       <code class="literal">
        Source_UUID
       </code>
      </td>
      <td>
       19
      </td>
      <td>
       The source's unique ID
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Retry_count
       </code>
      </th>
      <td>
       <code class="literal">
        Source_Retry_Count
       </code>
      </td>
      <td>
       20
      </td>
      <td>
       Maximum number of reconnection attempts permitted
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Ssl_crl
       </code>
      </th>
      <td>
       [None]
      </td>
      <td>
       21
      </td>
      <td>
       Path to an SSL certificate revocation-list file
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Ssl_crlpath
       </code>
      </th>
      <td>
       [None]
      </td>
      <td>
       22
      </td>
      <td>
       Path to a directory containing SSL certificate revocation-list files
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Enabled_auto_position
       </code>
      </th>
      <td>
       <code class="literal">
        Auto_position
       </code>
      </td>
      <td>
       23
      </td>
      <td>
       Whether GTID auto-positioning is in use or not
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Channel_name
       </code>
      </th>
      <td>
       <code class="literal">
        Channel_name
       </code>
      </td>
      <td>
       24
      </td>
      <td>
       The name of the replication channel
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Tls_version
       </code>
      </th>
      <td>
       <code class="literal">
        Source_TLS_Version
       </code>
      </td>
      <td>
       25
      </td>
      <td>
       TLS version on the source
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Public_key_path
       </code>
      </th>
      <td>
       <code class="literal">
        Source_public_key_path
       </code>
      </td>
      <td>
       26
      </td>
      <td>
       Name of the RSA public key file
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Get_public_key
       </code>
      </th>
      <td>
       <code class="literal">
        Get_source_public_key
       </code>
      </td>
      <td>
       27
      </td>
      <td>
       Whether to request RSA public key from source
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Network_namespace
       </code>
      </th>
      <td>
       <code class="literal">
        Network_namespace
       </code>
      </td>
      <td>
       28
      </td>
      <td>
       Network namespace
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Master_compression_algorithm
       </code>
      </th>
      <td>
       [None]
      </td>
      <td>
       29
      </td>
      <td>
       Permitted compression algorithms for the connection to the source
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Master_zstd_compression_level
       </code>
      </th>
      <td>
       [None]
      </td>
      <td>
       30
      </td>
      <td>
       <code class="literal">
        zstd
       </code>
       compression level
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Tls_ciphersuites
       </code>
      </th>
      <td>
       [None]
      </td>
      <td>
       31
      </td>
      <td>
       Permitted ciphersuites for TLSv1.3
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Source_connection_auto_failover
       </code>
      </th>
      <td>
       [None]
      </td>
      <td>
       32
      </td>
      <td>
       Whether the asynchronous connection failover mechanism is activated
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Gtid_only
       </code>
      </th>
      <td>
       [None]
      </td>
      <td>
       33
      </td>
      <td>
       Whether the channel uses only GTIDs and does not persist positions
      </td>
     </tr>
    </tbody>
   </table>
  </div>
  <div class="informaltable">
   <table cellpadding="0" cellspacing="0" style="position: fixed; top: 0px; display: none; left: 401px; width: 752px;">
    <thead>
     <tr>
      <th scope="col" style="width: 258.891px;">
       <code class="literal">
        slave_master_info
       </code>
       Table Column
      </th>
      <th scope="col" style="width: 242.641px;">
       <code class="literal">
        SHOW REPLICA STATUS
       </code>
       Column
      </th>
      <th scope="col" style="width: 96.3906px;">
       <code class="filename">
        master.info
       </code>
       File Line
      </th>
      <th scope="col" style="width: 153.266px;">
       Description
      </th>
     </tr>
    </thead>
   </table>
  </div>
  <p>
   For the applier metadata repository, the following table shows
        the correspondence between the columns in the
   <code class="literal">
    mysql.slave_relay_log_info
   </code>
   table, the columns
        displayed by
   <a class="link" href="show-replica-status.html" title="15.7.7.35 SHOW REPLICA STATUS Statement">
    <code class="literal">
     SHOW REPLICA STATUS
    </code>
   </a>
   ,
        and the lines in the deprecated
   <code class="filename">
    relay-log.info
   </code>
   file.
  </p>
  <div class="informaltable">
   <table summary="The correspondence between the columns in the mysql.slave_relay_log_info table, the columns displayed by SHOW REPLICA STATUS, and the lines in the deprecated relay-log.info file.">
    <colgroup>
     <col style="width: 30%"/>
     <col style="width: 40%"/>
     <col style="width: 15%"/>
     <col style="width: 20%"/>
    </colgroup>
    <thead>
     <tr>
      <th scope="col">
       <code class="literal">
        slave_relay_log_info
       </code>
       Table Column
      </th>
      <th scope="col">
       <code class="literal">
        SHOW REPLICA STATUS
       </code>
       Column
      </th>
      <th scope="col">
       Line in
       <code class="filename">
        relay-log.info
       </code>
       File
      </th>
      <th scope="col">
       Description
      </th>
     </tr>
    </thead>
    <tbody>
     <tr>
      <th scope="row">
       <code class="literal">
        Number_of_lines
       </code>
      </th>
      <td>
       [None]
      </td>
      <td>
       1
      </td>
      <td>
       Number of columns in the table or lines in the file
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Relay_log_name
       </code>
      </th>
      <td>
       <code class="literal">
        Relay_Log_File
       </code>
      </td>
      <td>
       2
      </td>
      <td>
       The name of the current relay log file
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Relay_log_pos
       </code>
      </th>
      <td>
       <code class="literal">
        Relay_Log_Pos
       </code>
      </td>
      <td>
       3
      </td>
      <td>
       The current position within the relay log file; events up to this
              position have been executed on the replica database
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Master_log_name
       </code>
      </th>
      <td>
       <code class="literal">
        Relay_Source_Log_File
       </code>
      </td>
      <td>
       4
      </td>
      <td>
       The name of the source's binary log file from which the events in the
              relay log file were read
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Master_log_pos
       </code>
      </th>
      <td>
       <code class="literal">
        Exec_Source_Log_Pos
       </code>
      </td>
      <td>
       5
      </td>
      <td>
       The equivalent position within the source's binary log file of the
              events that have been executed on the replica
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Sql_delay
       </code>
      </th>
      <td>
       <code class="literal">
        SQL_Delay
       </code>
      </td>
      <td>
       6
      </td>
      <td>
       The number of seconds that the replica must lag the source
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Number_of_workers
       </code>
      </th>
      <td>
       [None]
      </td>
      <td>
       7
      </td>
      <td>
       The number of worker threads for applying replication transactions in
              parallel
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Id
       </code>
      </th>
      <td>
       [None]
      </td>
      <td>
       8
      </td>
      <td>
       ID used for internal purposes; currently this is always 1
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Channel_name
       </code>
      </th>
      <td>
       <code class="literal">
        Channel_name
       </code>
      </td>
      <td>
       9
      </td>
      <td>
       The name of the replication channel
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Privilege_checks_username
       </code>
      </th>
      <td>
       [None]
      </td>
      <td>
       10
      </td>
      <td>
       The user name for the
       <code class="literal">
        PRIVILEGE_CHECKS_USER
       </code>
       account
              for the channel
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Privilege_checks_hostname
       </code>
      </th>
      <td>
       [None]
      </td>
      <td>
       11
      </td>
      <td>
       The host name for the
       <code class="literal">
        PRIVILEGE_CHECKS_USER
       </code>
       account
              for the channel
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Require_row_format
       </code>
      </th>
      <td>
       [None]
      </td>
      <td>
       12
      </td>
      <td>
       Whether the channel accepts only row-based events
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Require_table_primary_key_check
       </code>
      </th>
      <td>
       [None]
      </td>
      <td>
       13
      </td>
      <td>
       The channel's policy on whether tables must have primary keys for
       <code class="literal">
        CREATE TABLE
       </code>
       and
       <code class="literal">
        ALTER
              TABLE
       </code>
       operations
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Assign_gtids_to_anonymous_transactions_type
       </code>
      </th>
      <td>
       [None]
      </td>
      <td>
       14
      </td>
      <td>
       If the channel assigns a GTID to replicated transactions that do not
              already have one, using the replica's local UUID,
              this value is
       <code class="literal">
        LOCAL
       </code>
       ; if the channel
              does so using instead a UUID which has been set manually,
              the value is
       <code class="literal">
        UUID
       </code>
       . If the channel does
              not assign a GTID in such cases, the value is
       <code class="literal">
        OFF
       </code>
       .
      </td>
     </tr>
     <tr>
      <th scope="row">
       <code class="literal">
        Assign_gtids_to_anonymous_transactions_value
       </code>
      </th>
      <td>
       [None]
      </td>
      <td>
       15
      </td>
      <td>
       The UUID used in the GTIDs assigned to anonymous transactions
      </td>
     </tr>
    </tbody>
   </table>
  </div>
  <div class="informaltable">
   <table cellpadding="0" cellspacing="0" style="position: fixed; top: 0px; display: none; left: 401px; width: 793px;">
    <thead>
     <tr>
      <th scope="col" style="width: 364.516px;">
       <code class="literal">
        slave_relay_log_info
       </code>
       Table Column
      </th>
      <th scope="col" style="width: 177.641px;">
       <code class="literal">
        SHOW REPLICA STATUS
       </code>
       Column
      </th>
      <th scope="col" style="width: 72px;">
       Line in
       <code class="filename">
        relay-log.info
       </code>
       File
      </th>
      <th scope="col" style="width: 177.641px;">
       Description
      </th>
     </tr>
    </thead>
   </table>
  </div>
 </div>
 <br/>
</div>
