What do these in the slow log mean or do?
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# Time: 2019-02-17T12:22:03.737532Z
# User@Host: root[root] @ localhost [] Id: 1157990
# Query_time: 96.823558 Lock_time: 0.000000 Rows_sent: 11721867 Rows_examined: 11721867
SET timestamp=1550406123;
SELECT /*!40001 SQL_NO_CACHE */ * FROM `mdl_question`;
# Time: 2019-02-17T12:22:33.578746Z
# User@Host: root[root] @ localhost [] Id: 1157990
# Query_time: 29.557382 Lock_time: 0.000000 Rows_sent: 9471146 Rows_examined: 9471146
SET timestamp=1550406153;
SELECT /*!40001 SQL_NO_CACHE */ * FROM `mdl_question_answers`;
# Time: 2019-02-17T12:23:00.735374Z
# User@Host: root[root] @ localhost [] Id: 1157990
# Query_time: 27.150846 Lock_time: 0.000000 Rows_sent: 13651850 Rows_examined: 13651850
SET timestamp=1550406180;
SELECT /*!40001 SQL_NO_CACHE */ * FROM `mdl_question_attempt_step_data`;
# Time: 2019-02-17T12:23:22.124677Z
# User@Host: root[root] @ localhost [] Id: 1157990
# Query_time: 21.382610 Lock_time: 0.000000 Rows_sent: 12738531 Rows_examined: 12738531
SET timestamp=1550406202;
SELECT /*!40001 SQL_NO_CACHE */ * FROM `mdl_question_attempt_steps`;
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