61 lines
1.2 KiB
MySQL
61 lines
1.2 KiB
MySQL
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/* https://dev.mysql.com/doc/refman/8.0/en/explain.html */
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/* {EXPLAIN | DESCRIBE | DESC}
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tbl_name [col_name | wild]
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{EXPLAIN | DESCRIBE | DESC}
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[explain_type]
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{explainable_stmt | FOR CONNECTION connection_id}
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{EXPLAIN | DESCRIBE | DESC} ANALYZE [FORMAT = TREE] select_statement
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explain_type: {
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EXTENDED
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| PARTITIONS
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| FORMAT = format_name
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}
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format_name: {
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TRADITIONAL
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| JSON
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| TREE
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}
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explainable_stmt: {
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SELECT statement
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| TABLE statement
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| DELETE statement
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| INSERT statement
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| REPLACE statement
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| UPDATE statement
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} */
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EXPLAIN t1 c1;
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EXPLAIN t1 '%size%';
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DESC t1 '%size%';
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DESCRIBE t1;
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DESC t1;
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EXPLAIN SELECT * FROM t1;
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DESCRIBE FOR CONNECTION 'connection_id';
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DESCRIBE EXTENDED SELECT * FROM t1;
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DESC EXTENDED FOR CONNECTION 'connection_id';
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DESCRIBE PARTITIONS SELECT * FROM t1;
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DESC PARTITIONS FOR CONNECTION 'connection_id';
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DESC FORMAT = TRADITIONAL FOR CONNECTION 'connection_id';
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DESC FORMAT = JSON FOR CONNECTION 'connection_id';
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DESC FORMAT = TREE FOR CONNECTION 'connection_id';
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/* https://dev.mysql.com/doc/refman/8.0/en/help.html */
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HELP 'search_string';
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/* https://dev.mysql.com/doc/refman/8.0/en/use.html */
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USE db_name;
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