Numeric

Integer Data Types

Name	Alias	Size	Min Value	Max Value
TINYINT	INT8	1 byte	-128	127
SMALLINT	INT16	2 bytes	-32768	32767
INT	INT32	4 bytes	-2147483648	2147483647
BIGINT	INT64	8 bytes	-9223372036854775808	9223372036854775807

提示

如果您想要无符号整数，请使用 UNSIGNED 约束，它与 MySQL 兼容，例如：

CREATE TABLE test_numeric(tiny TINYINT, tiny_unsigned TINYINT UNSIGNED)

Floating-Point Data Types

Name	Size	Min Value	Max Value
FLOAT	4 bytes	-3.40282347e+38	3.40282347e+38
DOUBLE	8 bytes	-1.7976931348623157E+308	1.7976931348623157E+308

Functions

请参阅 Numeric Functions。

Examples

CREATE TABLE test_numeric
(
    tiny              TINYINT,
    tiny_unsigned     TINYINT UNSIGNED,
    smallint          SMALLINT,
    smallint_unsigned SMALLINT UNSIGNED,
    int               INT,
    int_unsigned      INT UNSIGNED,
    bigint            BIGINT,
    bigint_unsigned   BIGINT UNSIGNED,
    float             FLOAT,
    double            DOUBLE
);

DESC test_numeric;

Result:

┌───────────────────────────────────────────────────────────────────┐
│       Field       │        Type       │  Null  │ Default │  Extra │
├───────────────────┼───────────────────┼────────┼─────────┼────────┤
│ tiny              │ TINYINT           │ YES    │ NULL    │        │
│ tiny_unsigned     │ TINYINT UNSIGNED  │ YES    │ NULL    │        │
│ smallint          │ SMALLINT          │ YES    │ NULL    │        │
│ smallint_unsigned │ SMALLINT UNSIGNED │ YES    │ NULL    │        │
│ int               │ INT               │ YES    │ NULL    │        │
│ int_unsigned      │ INT UNSIGNED      │ YES    │ NULL    │        │
│ bigint            │ BIGINT            │ YES    │ NULL    │        │
│ bigint_unsigned   │ BIGINT UNSIGNED   │ YES    │ NULL    │        │
│ float             │ FLOAT             │ YES    │ NULL    │        │
│ double            │ DOUBLE            │ YES    │ NULL    │        │
└───────────────────────────────────────────────────────────────────┘