SQL data types are divided into five categories:
Character/Strings can be used to store strings like names, locations, etc. and even large text files.
| Data Type | Description | 
|---|---|
| CHAR | Maximum 8000 character long fixed length string | 
| VARCHAR | Maximum 8000 character long variable length string | 
| VARCHAR(max) | Maximum maxcharacter long variable length string | 
| NCHAR | Unicode Maximum 8000 character long fixed length string | 
| NVARCHAR | Unicode Maximum 8000 character long variable length string | 
| NVARCHAR(max) | Unicode Maximum maxcharacter long variable length string | 
| TEXT | Maximum 2GB sized variable length string | 
Numeric data types can be used to store exact or decimal numeric data, from very small numbers in a bit or tinyint to very large numbers in a bigint.
| Data Type | Minimum | Maximum | 
|---|---|---|
| bit | 0 | 1 | 
| tinyint | 0 | 255 | 
| smallint | -32,768 | 32,767 | 
| int | -2,147,483,648 | 2,147,483,647 | 
| bigint | -9,223,372,036,854,775,808 | 9,223,372,036,854,775,807 | 
| decimal | -10^38 - 1 | -10^38 - 1 | 
| real | -3.40E + 38 | 3.40E + 38 | 
| numeric | -10^38 +1 | 10^38 -1 | 
| float | -1.79E + 308 | 1.79E + 308 | 
Date/Time data types are used to store data and time objects. Storing a date as a date/type object instead of a string can make it very easy to work with data at a later point.
| Data Type | Description | 
|---|---|
| Datetime | Date and Time stored in the YYYY-MM-DD HH:MI:SS format | 
| Date | Date stored in the YYYY-MM-DD format | 
| Time | Time stored in the HH:MI:SS format | 
| Timestamp | Number of seconds passed stored since ‘1970-01-01 00:00:00’ UTC | 
| Year | Year stored in 2-digit (from 1970-2069) or 4-digit (from 1901 2155) format | 
Binary data types are used to store data in its binary form, instead of storing it as strings, which can be a big factor in saving space.
| Data Type | Description | 
|---|---|
| BINARY | Maximum length of 8000 bytes fixed binary | 
| VARBINARY | Maximum length of 8000 bytes variable binary | 
| VARBINARY(max) | Maximum length of maxbytes fixed binary | 
| NTEXT | Maximum 2GB sized variable length binary | 
These data types are for special types of data as described below:
| Data Type | Description | 
|---|---|
| CLOB | Upto 2GB large character objects | 
| BLOB | For storing binary large objects | 
| JSON | For storing JSON objects | 
| XML | For storing XML objects | 
Free Resources