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Displaying posts with tag: mariadb_performances (reset)

MariaDB/MySQL: Performances of COUNT()
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How fast is COUNT() execution? Well, it depends from the Storage Engine.

Try to create an Aria or MyISAM table, INSERT some data, and execute an EXPLAIN similar to the following:

MariaDB [(none)]> EXPLAIN SELECT COUNT(*) FROM test.t1;
+------+-------------+-------+------+---------------+------+--------+------+------+------------------------------+
| id   | select_type | table | type | possible_keys | key  | key_len | ref  | rows | Extra                        |
+------+-------------+-------+------+---------------+------+--------+------+------+------------------------------+
|    1 | SIMPLE      | NULL  | NULL | NULL          | NULL | NULL    | NULL | NULL |
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