mysql 数据类型转换

CAST(expr AS type), CONVERT(expr,type), CONVERT(expr USING transcoding_name)

The CAST() and CONVERT() functions take a value of one type and produce a value of another type.

The type can be one of the following values:

BINARY[(N)]

CHAR[(N)]

DATE

DATETIME

DECIMAL DECIMAL(12,4)

SIGNED [INTEGER]

TIME

UNSIGNED [INTEGER]

mysql> select cast(now() as char);