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     <h4 class="title">
      <a name="performance-schema-events-transactions-history-table">
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      29.12.7.2 The events_transactions_history Table
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  <p>
   The
   <a class="link" href="performance-schema-events-transactions-history-table.html" title="29.12.7.2 The events_transactions_history Table">
    <code class="literal">
     events_transactions_history
    </code>
   </a>
   table contains the
   <em class="replaceable">
    <code>
     N
    </code>
   </em>
   most recent
          transaction events that have ended per thread. Transaction
          events are not added to the table until they have ended. When
          the table contains the maximum number of rows for a given
          thread, the oldest thread row is discarded when a new row for
          that thread is added. When a thread ends, all its rows are
          discarded.
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  <p>
   The Performance Schema autosizes the value of
   <em class="replaceable">
    <code>
     N
    </code>
   </em>
   during server startup. To set the
          number of rows per thread explicitly, set the
   <a class="link" href="performance-schema-system-variables.html#sysvar_performance_schema_events_transactions_history_size">
    <code class="literal">
     performance_schema_events_transactions_history_size
    </code>
   </a>
   system variable at server startup.
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  <p>
   The
   <a class="link" href="performance-schema-events-transactions-history-table.html" title="29.12.7.2 The events_transactions_history Table">
    <code class="literal">
     events_transactions_history
    </code>
   </a>
   table has the same columns and indexing as
   <a class="link" href="performance-schema-events-transactions-current-table.html" title="29.12.7.1 The events_transactions_current Table">
    <code class="literal">
     events_transactions_current
    </code>
   </a>
   . See
   <a class="xref" href="performance-schema-events-transactions-current-table.html" title="29.12.7.1 The events_transactions_current Table">
    Section 29.12.7.1, “The events_transactions_current Table”
   </a>
   .
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  <p>
   <a class="link" href="truncate-table.html" title="15.1.37 TRUNCATE TABLE Statement">
    <code class="literal">
     TRUNCATE TABLE
    </code>
   </a>
   is permitted for
          the
   <a class="link" href="performance-schema-events-transactions-history-table.html" title="29.12.7.2 The events_transactions_history Table">
    <code class="literal">
     events_transactions_history
    </code>
   </a>
   table. It removes the rows.
  </p>
  <p>
   For more information about the relationship between the three
          transaction event tables, see
   <a class="xref" href="performance-schema-event-tables.html" title="29.9 Performance Schema Tables for Current and Historical Events">
    Section 29.9, “Performance Schema Tables for Current and Historical Events”
   </a>
   .
  </p>
  <p>
   For information about configuring whether to collect
          transaction events, see
   <a class="xref" href="performance-schema-transaction-tables.html" title="29.12.7 Performance Schema Transaction Tables">
    Section 29.12.7, “Performance Schema Transaction Tables”
   </a>
   .
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