I want to count errors by database user for IS.user_statistics. I have code that does it in my_message_sql but hfisk thinks the counts might be inflated. I don&#39;t understand the error reporting framework in MySQL so it is possible that the counts are wrong or count errors and warnings rather than only counting errors. The code below is from my_message_sql and shows where I try to maintain the count. The assignment (thd-&gt;is_slave_error= 1) makes me think that an error has occurred by the time I count it. But code that follows has comments about clearing an error or converting an error to a warning.<div>
<div><br></div><div><div>  if ((thd= current_thd))</div><div>  {</div><div>    /*</div><div>      TODO: There are two exceptions mechanism (THD and sp_rcontext),</div><div>      this could be improved by having a common stack of handlers.</div>
<div>    */</div><div>    if (thd-&gt;handle_error(error, str,</div><div>                          MYSQL_ERROR::WARN_LEVEL_ERROR))</div><div>      DBUG_RETURN(0);</div><div><br></div><div>    {</div><div>      USER_STATS *us= thd_get_user_stats(thd);    --------------------------------&gt; added by me</div>
<div>      my_atomic_add_bigint(&amp;(us-&gt;errors_total), 1);   --------------------------------&gt; added by me</div><div>    }</div><div><br></div><div>    thd-&gt;is_slave_error=  1; // needed to catch query errors during replication</div>
<div><br></div><div><div>    /*</div><div>      thd-&gt;lex-&gt;current_select == 0 if lex structure is not inited</div><div>      (not query command (COM_QUERY))</div><div>    */</div><div>    if (thd-&gt;lex-&gt;current_select &amp;&amp;</div>
<div>        thd-&gt;lex-&gt;current_select-&gt;no_error &amp;&amp; !thd-&gt;is_fatal_error)</div><div>    {</div><div>      DBUG_PRINT(&quot;error&quot;,</div><div>                 (&quot;Error converted to warning: current_select: no_error %d  &quot;</div>
<div>                  &quot;fatal_error: %d&quot;,</div><div>                  (thd-&gt;lex-&gt;current_select ?</div><div>                   thd-&gt;lex-&gt;current_select-&gt;no_error : 0),</div><div>                  (int) thd-&gt;is_fatal_error));</div>
<div>    }</div><div>    else</div><div>    {</div><div>      if (! thd-&gt;main_da.is_error())            // Return only first message</div><div>      {</div><div>        thd-&gt;main_da.set_error_status(thd, error, str);</div>
<div>      }</div><div>      query_cache_abort(&amp;thd-&gt;net);</div><div>    }</div><div>    /*</div><div>      If a continue handler is found, the error message will be cleared</div><div>      by the stored procedures code.</div>
<div>    */</div><div>    if (thd-&gt;spcont &amp;&amp;</div><div>        ! (MyFlags &amp; ME_NO_SP_HANDLER) &amp;&amp;</div><div>        thd-&gt;spcont-&gt;handle_error(error, MYSQL_ERROR::WARN_LEVEL_ERROR, thd))</div><div>
    {</div><div>      /*</div><div>        Do not push any warnings, a handled error must be completely</div><div>        silenced.</div><div>      */</div><div>      DBUG_RETURN(0);</div><div>    }</div><div><br></div><div>
    /* When simulating OOM, skip writing to error log to avoid mtr errors */</div><div>    DBUG_EXECUTE_IF(&quot;simulate_out_of_memory&quot;, DBUG_RETURN(0););</div><div><br></div><div>    if (!thd-&gt;no_warnings_for_error &amp;&amp;</div>
<div>        !(MyFlags &amp; ME_NO_WARNING_FOR_ERROR))</div><div>    {</div><div>      /*</div><div>        Suppress infinite recursion if there a memory allocation error</div><div>        inside push_warning.</div><div>      */</div>
<div>      thd-&gt;no_warnings_for_error= TRUE;</div><div>      push_warning(thd, MYSQL_ERROR::WARN_LEVEL_ERROR, error, str);</div><div>      thd-&gt;no_warnings_for_error= FALSE;</div><div>    }</div><div>  }</div><div><br>
</div><div>  /* When simulating OOM, skip writing to error log to avoid mtr errors */</div><div>  DBUG_EXECUTE_IF(&quot;simulate_out_of_memory&quot;, DBUG_RETURN(0););</div><div><br></div><div>  if (!thd || MyFlags &amp; ME_NOREFRESH)</div>
<div>    sql_print_error(&quot;%s: %s&quot;,my_progname,str); /* purecov: inspected */</div><div>  DBUG_RETURN(0);</div><div>}</div></div><div><br></div><div><br></div><br>-- <br>Mark Callaghan<br><a href="mailto:mdcallag@gmail.com">mdcallag@gmail.com</a><br>

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