How many sets of data types does MySQL support?

MySQL uses many different data types, divided into three categories -

• Numbers
• Date and Time
• String type

Numeric data type

MySQL uses all standard ANSI SQL numeric data types, so if you are starting from a different database System access to MySQL, these definitions will look familiar to you. p>

The following list shows the common numeric data types and their descriptions -

• INT – normal-sized integer, may be signed or unsigned. If signed, the allowed range is from -2147483648 to 2147483647. If unsigned, the allowed range is from 0 to 4294967295. You can specify a width of up to 11 bits.
• TINYINT – A very small integer that can be signed or unsigned. If signed, the allowed range is -128 to 127. If unsigned, the allowed range is 0 to 255. You can specify a width of up to 4 bits.
• SMALLINT – A small integer that can be signed or unsigned. If signed, the allowed range is -32768 to 32767. If unsigned, the allowed range is 0 to 65535. You can specify a width of up to 5 characters.
• MEDIUMINT – A medium-sized integer that can be signed or unsigned. If signed, the allowed range is -8388608 to 8388607. If unsigned, the allowed range is 0 to 16777215. You can specify a width of up to 9 bits.
• BIGINT – A large integer that can be signed or unsigned. If signed, the allowed range is from -9223372036854775808 to 9223372036854775807. If unsigned, the allowed range is from 0 to 18446744073709551615. You can specify a width of up to 20 bits.
• FLOAT(M,D) - Cannot be an unsigned floating point number. You can define the display length (M) and the number of decimal places (D). This is not required and defaults to 10,2, where 2 is the number of decimal places and 10 is the total number of digits (including decimal places). FLOAT can have decimal precision up to 24 digits.
• DOUBLE(M,D) – A cannot be an unsigned double precision floating point number. You can define the display length (M) and the number of decimal places (D).
• DECIMAL(M,D ) – Cannot unsign an unpacked floating point number. In the decompressed decimals, each decimal corresponds to one byte. The display length (M) and the number of decimal places (D) need to be defined. NUMERIC is a synonym for DECIMAL

This is not required and defaults to 16,4 where 4 is the number of decimal places. For DOUBLE, decimal precision can be up to 53 digits. REAL is a synonym for DOUBLE.

Date and time types

MySQL date and time data types are as follows-

• Date - The date range is between 1000-01-01 and 9999-12-31. "YYYY-MM-DD" is the default date format. For example, January 17, 1984 would be stored as 1984-01-17.
• DATETIME - This data type supports dates between 1000-01-01 00:00:00 and 9999-12-31 23:59:59 time. "YYYY-MM-DD HH:MM:SS" is the default DATETIME format. For example, January 17, 1984 at 2:20 PM would be stored as 1984-01-17 14:20:00.
• TIMESTAMP - Timestamp data type supports "1970-01-01 00:00:01" to "2038-01-19 08:44:07" between date and time'. It's just like the DATETIME data type. For example, January 17, 1984 at 2:20 PM would be stored as 1984-01-17 14:20:00.
• TIME - Stores the time in HH:MM:SS format.
• YEAR(M) - Stores the year in 2 or 4 digit format. If the length is specified as 2 (for example, YEAR(2)), YEAR can be between 1970 and 2069 (70 and 69). If length is specified as 4, YEAR can be 1901 to 2155. The default length is 4.

String Types

Although number and date types are interesting, most of the data you store will be stored in strings

Format. This list describes common string data types in MySQL.

• CHAR(M) – A fixed-length string between 1 and 1 with a length of 255 characters (e.g. CHAR(5)), right-padded with spaces to the specified length when stored . The length does not need to be defined, but the default value is 1.
• VARCHAR(M) – A variable-length string between 1 and 65,535 characters in length. For example, VARCHAR(25). The length must be defined when creating a VARCHAR field.
• BLOB or TEXT – A field with a maximum length of 65535 characters. BLOBs are "binary large objects" used to store large amounts of binary data, such as images or other types of files. Fields defined as TEXT also hold large amounts of data. The difference between the two is that sorting and comparisons of stored data are case-sensitive in BLOBs but not case-sensitive in TEXT fields. You don't need to use BLOB or TEXT to specify the length.
• TINYBLOB or TINYTEXT – A BLOB or TEXT column with a maximum length of 255 characters. You do not need to specify the length using TINYBLOB or TINYTEXT.
• MEDIUMBLOB or MEDIUMTEXT – A BLOB or TEXT column with a maximum length of 16777215 characters. You do not need to specify the length with MEDIUMBLOB or MEDIUMTEXT.
• LONGBLOB or LONGTEXT – A BLOB or TEXT column with a maximum length of 4294967295 characters. You do not need to use LONGBLOB or LONGTEXT to specify the length.
• ENUM – Enumeration, which is a fancy term for a list. When you define an ENUM, you are creating a list of items from which a value must be selected (or can be NULL). For example, if you want a field to contain 'A' or 'B' or 'C', you can define ENUM as ENUM('A', 'B', 'C') and only those values ​​(or NULL) can be populated this field.

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