MySQL parameter, mysql

MySQL parameter, mysql

1. SQL _safe_updates

The official explanation is as follows:

If set to 1, MySQL aborts UPDATE or DELETE statements that do not use a key in the WHERE clause or a LIMIT clause. (Specifically, UPDATE statements must have a WHERE clause that uses a key or a LIMIT clause, or both. DELETE statements must have both .) this makes it possible to catch UPDATE or DELETE statements where keys are not used properly and that wowould probably change or delete a large number of rows. the default value is 0.

The default value is 0. If it is set to 1, the delete and update operations must carry the where clause, and the columns in the where clause must be key or primary key, if no key or primary key is set during table design, the delete and update operations are not allowed. If the key or primary key is set during table design, however, the where clause specifies other columns, and the delete and update operations are also not allowed.