Java data type and MySQL data type correspondence table

Java MySQL data type comparison

Type name	Display length	Database type	Java type	JDBC Type index (int)	Describe
VARCHAR	L+n	VARCHAR	Java.lang.String	12
CHAR	N	CHAR	Java.lang.String	1
Blob	L+n	Blob	Java.lang.byte[]	-4
TEXT	65535	VARCHAR	Java.lang.String	-1
INTEGER	4	INTEGER UNSIGNED	Java.lang.Long	4
TINYINT	3	TINYINT UNSIGNED	Java.lang.Integer	-6
SMALLINT	5	SMALLINT UNSIGNED	Java.lang.Integer	5
Mediumint	8	Mediumint UNSIGNED	Java.lang.Integer	4
BIT	1	BIT	Java.lang.Boolean	-7
BIGINT	20	BIGINT UNSIGNED	Java.math.BigInteger	-5
FLOAT	4+8	FLOAT	Java.lang.Float	7
DOUBLE	22	DOUBLE	Java.lang.Double	8
DECIMAL	11	DECIMAL	Java.math.BigDecimal	3
BOOLEAN	1	With tinyint
Id	11	PK (INTEGER UNSIGNED)	Java.lang.Long	4
DATE	10	DATE	Java.sql.Date	91
Time	8	Time	Java.sql.Time	92
Datetime	19	Datetime	Java.sql.Timestamp	93
TIMESTAMP	19	TIMESTAMP	Java.sql.Timestamp	93
Year	4	Year	Java.sql.Date	91

for Bolb, generally used for the database storage of pictures, the principle is to make the picture into binary, and then do a storage method, in Java corresponding to the byte[] array.

for the Boolen type, in the MySQL database, the individual think that using the int type is better, the bit operation is not very convenient, especially in the project with Web page development, represents 0/1, corresponding to the Java type of integer is better. the declaration syntax for the decimal column is decimal (m,d). In mysql5.1, the value range of the parameter:
1, M is the maximum number (precision) of the number. The range is 1~65 (in the older MySQL version, the allowable range is 1~254).
2, D is the number of digits to the right of the decimal point (scale). Its scope is 0~30, but must not exceed M.
Description: Float accounted for 4 bytes, double was 8 bytes, decimail (m,d) accounted for m+2 bytes.
The maximum value for decimal (5, 2) is 9 9 9 9. 9 9, because there are 7 bytes available.

Java data type and MySQL data type correspondence table