MySQL supports a number of data types in several categories: numeric
types, date and time types, and string (character) types. This
chapter first gives an overview of these data types, and then
provides a more detailed description of the properties of the types
in each category, and a summary of the data type storage
requirements. The initial overview is intentionally brief. The more
detailed descriptions later in the chapter should be consulted for
additional information about particular data types, such as the
allowable formats in which you can specify values.
MySQL also supports extensions for handing spatial data.
Chapter 18, Spatial Extensions, provides information about
these data types.
Several of the data type descriptions use these conventions:
maximum display width for integer types. For floating-point and
M is the total
number of digits. For string types,
is the maximum length. The maximum allowable value of
M depends on the data type.
floating-point and fixed-point types and indicates the number of
digits following the decimal point. The maximum possible value
is 30, but should be no greater than
Square brackets (‘
]’) indicate optional parts of