mysql注释方法一:使用#
mysql> mysql> SELECT 1+1; # This comment continues to the end of line +-----+ | 1+1 | +-----+ | 2 | +-----+ 1 row in set (0.00 sec) mysql>
mysql注释方法二:使用--
mysql> mysql> SELECT 1+1; -- This comment continues to the end of line +-----+ | 1+1 | +-----+ | 2 | +-----+ 1 row in set (0.00 sec)
mysql注释方法三:使用/* */
mysql> mysql> mysql> SELECT 1 /* this is an in-line comment */ + 1; +---------+ | 1 + 1 | +---------+ | 2 | +---------+ 1 row in set (0.00 sec) mysql> SELECT 1+ -> /* /*> this is a /*> multiple-line comment /*> */ -> 1; +-------+ | 1+ 1 | +-------+ | 2 | +-------+ 1 row in set (0.00 sec) mysql>
mysql注释方法四:使用/*! */
mysql> mysql> mysql> CREATE /*!32302 TEMPORARY */ TABLE t (a INT); Query OK, 0 rows affected (0.02 sec) mysql> mysql> desc t; +-------+---------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +-------+---------+------+-----+---------+-------+ | a | int(11) | YES | | NULL | | +-------+---------+------+-----+---------+-------+ 1 row in set (0.00 sec) mysql> mysql> mysql> drop table t; Query OK, 0 rows affected (0.00 sec) mysql>
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