MySQL数据库学习四 存储引擎和数据类型

4.1存储引擎

   1. 查看MySQL DBMS所支持的存储引擎

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" alt="" />

SHOW VARIABLES LIKE 'have%';

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" alt="" />

Yes表示支持,No表示不支持,DISABLED表示支持但是未开启。

  2. 查询默认存储引擎

SHOW VARIABLES LIKE 'storage_engine%';

  3. 修改默认存储引擎

打开my.ini配置文件,修改[mysqld]中的default-storage-engine参数,重启MySQL服务。

4.2 数据类型

  4.2.1 整数类型

支持标准SQL中的所有整数类型(SMALLINT和INT/INTEGER),扩展增加了TINYINT、MEDIUMINT和BIGINT。

整数类型 字节 最小值 最大值
TINYINT 1

-128

0

127

255

SMALLINT 2

-2^15

0

2^15-1

2^16-1

MEDIUMINT 3

-2^23

0

2^23-1

2^24-1

INT/INTEGER 4

-2^31

0

2^31-1

2^32-1

BIGINT 8

-2^63

0

2^63-1

2^64-1

TINYINT类型占一个字节,最大值二进制:01111111,即127;最小值二进制:10000000,即-128.

  4.2.2 浮点数类型、定点数类型和位类型

1. 浮点型类型FLOAT、DOUBLE

浮点型类型 字节 最小值 最大值
FLOAT 4  ±1.75494351E-38  ±3.402823466E+38
DOUBLE 8  ±1.225073858072014E-308  ±1.7976931348623157E+308

当需要精确到小数点后10位以上,需要选择DOUBLE类型。

2. 定点数类型DEC(M,D)

定点数类型 字节 最小值 最大值
DEC(M,D)/DECIMAL(M,D) M+2 与DOUBLE相同 与DOUBLE相同

FLOAT、DOUBLE数据类型存储数据时存储的是近似值,而DECIMAL存储的是字符串,因此提供了更高的精度。

3. 位类型BIT(M)

位类型 字节 最小值 最大值
BIT(M) 1~8 BIT(0) BIT(64)

位类型的字节数为M,M的取值范围为1~8.

  4.2.3 日期和时间类型

日期和时间类型 字节 最小值 最大值
DATE 4 1000-01-01 9999-12-31
DATETIME 8 1000-01-01 00:00:00 9999-12-31 23:59:59
TIMESTAMP 4 19700101080001 2038年的某个时刻
TIME 3 -835:59:59 838:59:59
YEAR 1 1901 2155

如果需要经常插入或者更新日期为当前系统时间,一般会使用TIMESTAMP类型;

如果要表示年份,一般会使用占用空间更少的YEAR类型。

  4.2.4 字符串类型

1. CHAR系列

CHAR系列字符串类型 字节 描述
CHAR(M) M M为0~255之间的整数
VARCHAR(M) M M为0~65535之间的整数

如果要存储少量字符串,则可以选择CHAR和VARCHAR类型。如果存储字符串长度经常发生变化,则可以选择VARCHAR类型,否则选择CHAR类型。

2. TEXT系列

TEXT系列字符串类型 字节 描述
TINYTEXT 0~255 值的长度为2个字节
TEXT 0~65 535 值的长度为2个字节
MEDIUMTEXT 0~16 777 215 值的长度为4个字节
LONGTEXT 0~4 294 967 295 值的长度为8个字节

如果需要存储大量字符串(存储文字内容的纯文本),则可以选择TEXT系列字符串类型。

3. BINARY系列

BINARY系列字符串类型 字节 描述
BINARY(M) M 允许长度为0~M
VARBINARY(M) M 允许长度为0~M

如果需要存储少量二进制数据,可以选择BINARY和VARBINARY类型。如果存储二进制数据长度的发生变化,则可以选择VARBINARY类型,否则选择BINARY类型。

前者可以存储二进制数据(例如图片、音乐或视频文件),后者只能存储字符数据。

4. BLOB系列

BLOB系列字符串类型 字节
TINYBLOB 0~255
BLOB 0~2^16-1
MEDIUMBLOB 0~2^24-1
LONGBLOB 0~2^32-1

如果需要存储大量二进制数据(电影等视频文件),则可以选择BLOB系列字符串类型。

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