Learning MySQL data type (iv)

First, integer Type :

Integer type Bytes occupied Minimum value Maximum Value TINYINT 1 Signed-128 Unsigned 0 Signed 127 Unsigned 255 SMALLINT 2 Signed-3 2768 Unsigned 0 Signed 3 2767 Unsigned 6 5535 Mediumint 3 Signed-83 8608 Unsigned 0 Signed 838 8607 Unsigned 1677 7215 Int/integer 4 Signed-21 4748 3648 Unsigned 0 unsigned 21 4748 3647 Unsigned 42 9496 7295 BIGINT 8 Signed -9E19 Unsigned 0 Signed 9E19 unsigned 1E20

Second, floating-point type:

Determine which floating-point type to use, according to the actual situation, when the need to be accurate to 10 digits after the decimal point, you need to select Double.

Floating-point type	Bytes occupied	Minimum value	Maximum Value
FLOAT	4	±1.75494651e-38	±3.402823466e+38
DOUBLE	8	±2.2250738585072014e-308	±1.7976931348623157e+308

Second, String Type

1. 1. CHAR Series String

Stores a small number of characters. If the stored string length changes frequently, you can choose varchar.

String type	Bytes occupied	Describe
CHAR (M)	M	M is an integer between (0 ~ 255)
VARCHAR (M)	M	M is an integer between (0 ~ 6 5535)

1. 2. TEXT Series String

String type	Bytes occupied	Describe
Tinytext	0~255	the length of the value is +2 of bytes
TEXT	0~6 5535	the length of the value is +2 of bytes
Mediumtext	0~1 6777 2150	the length of the value is +3 of bytes
Longtext	0~42 9496 7295	the length of the value is +4 of bytes

1. 3. BINARY Series String

Very similar to the Char series, but binary can store binary data (picture, audio, video). When the stored binary data length changes frequently, you can choose varbinary.

String type	Bytes occupied	Describe
BINARY (M)	M	allow length to 0~m
VARBINARY (M)	M	allow length to 0~m

1. 4. BLOB Series String

Similar to the text series, but BLOBs can store binary data (picture, audio, video).

String type	Bytes
Tinyblob	0~255
Blob	0~2 of the - Sub-party (64KB)
Mediumblob	0~2 of the - Sub-party (16MB)
Longblob	0~2 of the + Sub-party (4GB)

Third, date and Time type

Date and Time type	Bytes occupied	Minimum value	Maximum Value
DATE	4	1000-01-01	9999-12-31
Daettime	8	1000-01-01 00:00:00	9999-12-31 23:59:59
TIMESTAMP	4	19700101080001	2038 at some point
Time	3	-835:59:59	835:59:59
Year	1	1901	2155

Four, fixed-point number types

　　　　The range of valid values, determined by M and D.

Fixed-point number types	Bytes occupied	Minimum value	Maximum Value
DEC (m,d)/decial (m,d)	M+2	Same as Double	Same as Double

Five, bit type

Bit type	Bytes occupied	Minimum value	Maximum Value
BIT (M)	1~8	BIT (1)	BIT (64)

Learning MySQL data type (iv)