Data type mapping occurs at table creation time, after which the original type specifications are discarded. : Introduction « Data Types « MySQL Tutorial






mysql>
mysql> CREATE TABLE t (a BOOL, b FLOAT8, c LONG VARCHAR, d NUMERIC);
Query OK, 0 rows affected (0.01 sec)

mysql>
mysql> DESCRIBE t;
+-------+---------------+------+-----+---------+-------+
| Field | Type          | Null | Key | Default | Extra |
+-------+---------------+------+-----+---------+-------+
| a     | tinyint(1)    | YES  |     | NULL    |       |
| b     | double        | YES  |     | NULL    |       |
| c     | mediumtext    | YES  |     | NULL    |       |
| d     | decimal(10,0) | YES  |     | NULL    |       |
+-------+---------------+------+-----+---------+-------+
4 rows in set (0.00 sec)

mysql>
mysql> drop table t;
Query OK, 0 rows affected (0.00 sec)








10.16.Introduction
10.16.1.The basic datatypes
10.16.2.Date Datatypes
10.16.3.Numeric Types Storage
10.16.4.Numeric Types
10.16.5.ZEROFILL,UNSIGNED,SERIAL,SERIAL DEFAULT VALUE
10.16.6.Using Data Types from Other Database Engines
10.16.7.Data type mapping occurs at table creation time, after which the original type specifications are discarded.
10.16.8.Storage Requirements for Numeric Types
10.16.9.Storage Requirements for Date and Time Types
10.16.10.The format of the zero value for each type.