explain

根據上面提到的explain去比較，就可以得出結果了

mysql> explain select * from users limit 1000,20;

+----+-------------+-------+------+---------------+------+---------+------+--------+-------+

| id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra |

+----+-------------+-------+------+---------------+------+---------+------+--------+-------+

| 1 | SIMPLE | users | ALL | NULL | NULL | NULL | NULL | 169847 | |

+----+-------------+-------+------+---------------+------+---------+------+--------+-------+

1 row in set (0.00 sec)

mysql> explain select * from users where uid>1000 limit 20;

+----+-------------+-------+-------+---------------+---------+---------+------+-------+-------------+

| id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra |

+----+-------------+-------+-------+---------------+---------+---------+------+-------+-------------+

| 1 | SIMPLE | users | range | PRIMARY | PRIMARY | 4 | NULL | 84923 | Using where |

+----+-------------+-------+-------+---------------+---------+---------+------+-------+-------------+

1 row in set (0.00 sec)

mysql> explain select * from users where uid between 1000 and 1020;

+----+-------------+-------+-------+---------------+---------+---------+------+------+-------------+

| id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra |

+----+-------------+-------+-------+---------------+---------+---------+------+------+-------------+

| 1 | SIMPLE | users | range | PRIMARY | PRIMARY | 4 | NULL | 1 | Using where |

+----+-------------+-------+-------+---------------+---------+---------+------+------+-------------+

1 row in set (0.00 sec)

總結

以上是生活随笔為你收集整理的mysql分析sql语句性能_sql语句执行性能分析的全部內容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網站內容還不錯，歡迎將生活随笔推薦給好友。