请教两条语句那条速度更快

Question

set profiling=1;
执行sql1;
执行sql2;
show profiles;

Answer 1

分别用explain看看执行计划  如果都执行飞快 真的没必要纠结用哪个

Answer 2

谢谢。结果是  语句2是比语句1更快。  看来我理解错了。。+----------+------------+-------------------------------------------------------
--------------------------------------------------------------------------------
-------------------+
| Query_ID | Duration   | Query                   |
+----------+------------+-------------------------------------------------------
--------------------------------------------------------------------------------
-------------------+
|        1 | 0.00401850 | 
                   |
|        2 | 0.00376700 |  |

Answer 3

干嘛不用内连接 ？ INNER JOIN