Security update mode in MySQL

The following error was reported when deleting data from a table in MySQL:

mysql> delete from upload_images;
ERROR 1175 (HY000): You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column

mysql> show variables like '%sql_safe%';
+------------------+-------+
| Variable_name    | Value |
+------------------+-------+
| sql_safe_updates | ON    |
+------------------+-------+
1 row in set (0.00 sec)

mysql> set sql_safe_updates=0;

Query OK, 0 rows affected (0.00 sec)

mysql> show variables like '%sql_safe%';
+------------------+-------+
| Variable_name    | Value |
+------------------+-------+
| sql_safe_updates | OFF   |
+------------------+-------+
1 row in set (0.00 sec)

mysql> delete from upload_images;
Query OK, 505 rows affected (0.01 sec)

And then enable Safe mode.

Mysql> set Sql_safe_updates=1;

This article is from the "Shadow Knight" blog, please be sure to keep this source http://andylhz2009.blog.51cto.com/728703/947634