ifnull

description

Syntax

ifnull(expr1, expr2)

如果 expr1 的值不为 NULL 则返回 expr1，否则返回 expr2

example

mysql> select ifnull(1,0);
+--------------+
| ifnull(1, 0) |
+--------------+
|            1 |
+--------------+
mysql> select ifnull(null,10);
+------------------+
| ifnull(NULL, 10) |
+------------------+
|               10 |
+------------------+

keywords

IFNULL