话说MySQL <>和！=

摘要: 话说MySQL <>和！= 有木有区别

话说MySQL两种不等号（！=和<>）：

《MySQL必知必会》P37页的6.2.2不匹配检查末有

SELECT vend_id,prod_name

FROM products

WHERE vend_id !=1003;

和

SELECT vend_id，prod_name

FROM products

WHERE vend_id <>1003;

想说明<>和！=有什么区别，结果是：

The != operator is converted to <> in the parser stage. It is not possible to implement != and <> operators that do different things.

没区别。。。

参考：1、http://stackoverflow.com/questions/7040305/whats-the-difference-between-and-in-mysql
2、http://www.sql.org/sql-database/postgresql/manual/functions-comparison.html