Java entity properties correspond to MySQL and SQL Server and Oracle data types

1:java data type and MySQL data type comparison table

Type name	Display length	Database type	Java type	JDBC Type index (int)
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 image database storage, 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.

2:sqlserver database corresponds to data type in Java

SQL Server Type	JDBC Type (java.sql.Types)	Java Language Types
bigint	BIGINT	Long
Timestamp Binary	BINARY	Byte[]
Bit	BIT	Boolean
Char	CHAR	String
Decimal Money SmallMoney	DECIMAL	Java.math.BigDecimal
Float	DOUBLE	Double
Int	INTEGER	Int
Image varbinary (max)	LongVarBinary	Byte[]
varchar (max) Text	LongVarChar	String
NChar	CHAR NCHAR (Java SE 6.0)	String
nvarchar	VARCHAR NVARCHAR (Java SE 6.0)	String
nvarchar (max) ntext	LongVarChar Longnvarchar (Java SE 6.0)	String
Numeric	NUMERIC	Java.math.BigDecimal
Real	REAL	Float
smallint	SMALLINT	Short
Datetime smalldatetime	TIMESTAMP	Java.sql.Timestamp
varbinary Udt	VARBINARY	Byte[]
varchar	VARCHAR	String
tinyint	TINYINT	Short
uniqueidentifier	CHAR	String
Xml	LongVarChar SQLXML (Java SE 6.0)	String SQLXML
Time	Time (1)	Java.sql.Time (1)
Date	DATE	Java.sql.Date
DateTime2	TIMESTAMP	Java.sql.Timestamp
DateTimeOffset (2)	Microsoft.sql.Types.DATETIMEOFFSET	Microsoft.sql.DateTimeOffset

3: SQL Server and Oracle data type correspondence

SQL Server 2k conversion to Oracle 10g

Column Name	SQL Server Data type	SQL Server length	Oracle data types
Column1	bigint	8	Number (19)
Column2	Binary	50	RAW (50)
Column3	Bit	1	Number (2)
Column4	Char	10	CHAR (10)
Column5	Datetime	8	DATE
Column6	Decimal	9	Number (18)
Column7	Float	8	Binary_double
Column8	Image	16	Blob
Column9	Int	4	Number (10)
Column10	Money	8	Number (19,4)
Column11	NChar	10	NCHAR (10)
Column12	ntext	16	NCLOB
Column13	Numeric	9	Number (18)
Column14	nvarchar	50	NVARCHAR2 (50)
Column15	Real	4	Binary_float
Column16	smalldatetime	4	DATE
Column17	smallint	2	Number (5)
Column18	SmallMoney	4	Number (10,4)
Column19	sql_variant		Blob
Column20	Text	16	Clob
Column21	Timestamp	8	RAW (8)
Column22	tinyint	1	Number (3)
Column23	uniqueidentifier	16	Blob
Column24	varbinary	50	RAW (50)
Column25	varchar	50	VARCHAR2 (50)

Oracle 10g translates to SQL Server 2k

Oracle Column Name	Oracle data types	SQL Server Column Name	SQL Server Data type	SQL Server Data length
COLUMN1	Binary_double	COLUMN1	Float	8
COLUMN2	Binary_float	COLUMN2	Real	4
COLUMN3	Blob	COLUMN3	Image	16
COLUMN4	Clob	COLUMN4	ntext	16
COLUMN5	CHAR (10)	COLUMN5	NChar	10
COLUMN6	DATE	COLUMN6	Datetime	8
COLUMN12	Number	COLUMN12	Numeric	13
COLUMN13	NVARCHAR2 (10)	COLUMN13	nvarchar	10
COLUMN14	RAW (10)	COLUMN14	varbinary	10
COLUMN15	TIMESP (6)	COLUMN15	Datetime	8
COLUMN16	TIMESP (6) with LOCAL time ZONE	COLUMN16	Datetime	8
COLUMN17	TIMESP (6) with time ZONE	COLUMN17	Datetime	8
COLUMN18	VARCHAR2 (10)	COLUMN18	nvarchar	10
COLUMN7	INTERVAL Day (2) to SECOND (6)	COLUMN7	nvarchar	30
COLUMN8	INTERVAL year (2) to MONTH	COLUMN8	nvarchar	14
COLUMN9	LONG	COLUMN9	ntext	16
COLUMN10	LONG RAW	COLUMN10	Image	16
COLUMN11	NCLOB	COLUMN11	ntext	16

The above are excerpts from a number of blog finishing.

Java entity properties correspond to MySQL and SQL Server and Oracle data types