<h2>Call Stack</h2>
<ol>
<li>in
<a class="toggle" title="black/src/app/vendor/topthink/think-mongo/src/Connection.php line 291">Connection.php line 291</a>
</li>
<li>
at
<abbr title="MongoDB\Driver\Manager">Manager</abbr>->executeQuery('mdb_mid_m2.m2_mid',
<em>object</em>(
<abbr title="MongoDB\Driver\Query">Query</abbr>),
<em>null</em>) in
<a class="toggle" title="/black/src/app/vendor/topthink/think-mongo/src/Connection.php line 291">Connection.php line 291</a>
</li>
<li>
at
<abbr title="think\mongo\Connection">Connection</abbr>->query('mdb_mid_m2.m2_mid',
<em>object</em>(
<abbr title="MongoDB\Driver\Query">Query</abbr>),
<em>null</em>,
<em>false</em>, ['root' => 'array', 'document' => 'array']) in
<a class="toggle" title="/black/src/app/vendor/topthink/think-mongo/src/Query.php line 254">Query.php line 254</a>
</li>
<li>
at
<abbr title="think\mongo\Query">Query</abbr>->query('m2_mid',
<em>object</em>(
<abbr title="MongoDB\Driver\Query">Query</abbr>),
<em>null</em>,
<em>false</em>, ['root' => 'array', 'document' => 'array']) in
<a class="toggle" title="/black/src/app/vendor/topthink/think-mongo/src/Query.php line 1746">Query.php line 1746</a>
</li>
<li>
at
<abbr title="think\mongo\Query">Query</abbr>->select() in
<a class="toggle" title="/black/src/app/application/index/mongo/Midm2.php line 62">Midm2.php line 62</a>
</li>
<li>
