MySql data types: how to understand and use
MySql is an open source relational database management system that supports multiple data types. These data types enable developers to create smarter and richer applications. Therefore, familiarity with MySql's data types is crucial for database managers and developers.
- Numeric data types
MySQL supports multiple numeric data types, including integer and floating point types. Integer types include:
- TINYINT (-128~127)
- SMALLINT (-32,768~32,767)
- MEDIUMINT (-8,388,608~8,388,607)
- INT or INTEGER (-2,147,483,648~2,147,483,647)
- BIGINT (-9,223,372,036,854,775,808~9,223,372,036,854,775,807)
Floating point types include:
- FLOAT (single Precision)
- DOUBLE (double precision)
- DECIMAL (fixed point number)
Understanding MySQL’s numeric data types can help us make the right choice and improve SQL Statement performance.
- String data type
MySQL supports multiple string data types, including:
- CHAR
- VARCHAR
- TINYTEXT
- TEXT
- MEDIUMTEXT
- LONGTEXT
- ENUM
- SET
The length and characteristics of these data types are different, so we need to choose according to the actual situation. For example, the CHAR type is suitable for fixed-length data, while VARCHAR is suitable for variable-length data.
- Date and time data types
MySql supports multiple date and time data types, including:
- DATE
- TIME
- YEAR
- DATETIME
- TIMESTAMP
These data types can store various time information such as date, time, year and time stamp. The methods of storing and retrieving these data types are also different, and we need to understand the characteristics of the data types and pay attention when reading and writing data.
- Other data types
MySql also supports other types of data, such as:
- BLOB (Binary Large Object)
- LONGBLOB, MEDIUMBLOB and TINYBLOB
- BINARY and VARBINARY
- BOOLEAN
These data types can be used to store large data such as pictures, audio and video, and also Can be used to store binary files and boolean values.
In short, mastering the different data types of MySql can help us better manage the database and develop more efficient and intelligent applications. When using MySql, we need to choose the appropriate data type according to specific needs, and pay attention to the characteristics and usage of the data type when storing and retrieving data.
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