Common MSSQLServer Data Types

Category 1: Integer Data

Bit: the BIT data type is 0, 1 or null, which means true, False . Occupies 1 byte.

Int : Stores Positive and Negative Numbers in 4 bytes. The storage range is: - 2 ^ 31 to 2 ^ 31 - 1 .

Smallint: stores Positive and Negative Numbers in 2 bytes. The storage range is: - 2 ^ 15 to 2 ^ 15 - 1

Tinyint: The smallest integer type. It must be 1 byte in the range of 0 to this point. ^ 8 - 1  



Second category: exact value data



Numeric: The number can reach 38 BITs. The number of bytes used for data storage varies with the number of used bits.

Decimal : Similar to numeric



Category 3: Approximate floating point data



Float : Uses 8 bytes to store data. A maximum of 53 bits are allowed. The range is: - 1 . 79E + 308 to 1.79e + 308 .

Real: the number of digits is 24, with 4 bytes. The value range is: - 3 . 04e + 38 to 3.04e + 38  



Category 4: Date and Time Data



Datatime: indicates that the time range can be expressed from 1753 / 1 / 1 to 9999 / 12 / 31 , Time can be expressed as 3. 33 / 1000 seconds. 8 bytes are used.

Smalldatetime: indicates that the time range can be expressed from 1900 / 1 / 1 To 2079 / 12 / 31 . Use 4 bytes.



Category 5: String data



Char : The length is set. The shortest value is 1 byte and the maximum value is 8000 bytes. The insufficient length will be filled with blank space.

Varchar: The length is also set. The shortest value is 1 byte and the maximum value is 8000 bytes. The white space at the end is removed.

Text: the length and width are also set. up to 2 GB data can be stored.



Category 6: unincode string data



Nchar: The length is set. The minimum value is 1 byte and the maximum value is 4000 bytes. The length is left blank. 2 bytes are required to store a character.

Nvarchar: Specifies the length. The minimum length is 1 byte and the maximum length is 4000 bytes. The white space at the end is removed. It takes 2 bytes to store a character.

Ntext: The length is set. The minimum value is 1 byte and the maximum value is 2 GB. The white space at the end is removed. It takes 2 bytes to store a character.



Category 7: currency data type



Money: The recorded amount range is: - 92233720368577 . 5808 to 92233720368577. 5807 . 8 bytes required.

Smallmoney: The recorded amount range is: - 214748 . 3648 to 214748. 36487 . 4 bytes required.



Category 8: Mark data



Timestamp: the data type is unique in each table. ! when a record in the table is changed, the timestamp field of the record is automatically updated.
uniqueidentifier: used to identify the unique record of many tables in the database.
Category 9: binary string data
binary: A fixed-length binary string field. The minimum value is 1 and the maximum value is 8000.
varbinary: When the tail of the data is 00, varbinary removes it
image: a variable-length binary string, the maximum length is 2 GB.