MySQL InnoDB Engine--数据页存储和DML操作

测试环境：

MySQL 5.7.28 社区版
CentOS release 6.10

MySQL Undo参数配置：
innodb_undo_tablespaces = 1
innodb_default_row_format = dynamic

测试1：插入测试

测试脚本：

## 创建测试表
CREATE TABLE `TB001` (
  `ID` VARCHAR(20) NOT NULL,
  `C1` VARCHAR(20) NOT NULL,
  `C2` VARCHAR(20) NOT NULL,
  PRIMARY KEY (`ID`),
  KEY `IDX_C1` (`C1`)
) ENGINE=INNODB DEFAULT CHARSET=utf8;

## 第一次插入数据
INSERT INTO `TB001`(ID,C1,C2)VALUES('AA0001','BB0001','CC0001'),('AA0002','BB0002','CC0002'),('AA0003','BB0003','CC0003');

## 第二次插入数据
INSERT INTO `TB001`(ID,C1,C2)VALUES('AA0004','BB0004','CC0004');

## 查看数据
SELECT * FROM TB001;
+--------+--------+--------+
| ID     | C1     | C2     |
+--------+--------+--------+
| AA0001 | BB0001 | CC0001 |
| AA0002 | BB0002 | CC0002 |
| AA0003 | BB0003 | CC0003 |
| AA0004 | BB0004 | CC0004 |
+--------+--------+--------+

叶子节点数据：

## 主键索引叶子节点数据
06 06 06 00 00 10 00 27 41 41 30 30 30 31 00 00 00 00 05 41 AE 00 00 00 70 01 10 42 42 30 30 30 31 43 43 30 30 30 31 
06 06 06 00 00 18 00 27 41 41 30 30 30 32 00 00 00 00 05 41 AE 00 00 00 70 01 1E 42 42 30 30 30 32 43 43 30 30 30 32 
06 06 06 00 00 20 00 27 41 41 30 30 30 33 00 00 00 00 05 41 AE 00 00 00 70 01 2C 42 42 30 30 30 33 43 43 30 30 30 33 
06 06 06 00 00 28 FF 7B 41 41 30 30 30 34 00 00 00 00 05 46 B1 00 00 00 73 01 10 42 42 30 30 30 34 43 43 30 30 30 34

## 索引IDX_C1叶子节点数据
06 06 00 00 10 00 13 42 42 30 30 30 31 41 41 30 30 30 31 
06 06 00 00 18 00 13 42 42 30 30 30 32 41 41 30 30 30 32 
06 06 00 00 20 00 13 42 42 30 30 30 33 41 41 30 30 30 33 
06 06 00 00 28 FF B8 42 42 30 30 30 34 41 41 30 30 30 34

测试2：更新测试

测试脚本：

## 更新C1列并导致数据变化
UPDATE TB001 SET C1='BBBB01' WHERE ID='AA0001';
## 更新C1列但不导致数据变化
UPDATE TB001 SET C1='BB0002' WHERE ID='AA0002';
## 更新C2列并导致数据变化
UPDATE TB001 SET C2='CCCC03' WHERE ID='AA0003';
## 更新C2列但不导致数据变化
UPDATE TB001 SET C2='CC0004' WHERE ID='AA0005';

SELECT * FROM TB001;
+--------+--------+--------+
| ID     | C1     | C2     |
+--------+--------+--------+
| AA0001 | BBBB01 | CC0001 |
| AA0002 | BB0002 | CC0002 |
| AA0003 | BB0003 | CCCC03 |
| AA0004 | BB0004 | CC0004 |
+--------+--------+--------+

叶子节点数据：

## 主键索引叶子节点数据
06 06 06 00 00 10 00 27 41 41 30 30 30 31 00 00 00 00 05 4F 38 00 00 00 91 04 6C 42 42 42 42 30 31 43 43 30 30 30 31 
06 06 06 00 00 18 00 27 41 41 30 30 30 32 00 00 00 00 05 41 AE 00 00 00 70 01 1E 42 42 30 30 30 32 43 43 30 30 30 32 
06 06 06 00 00 20 00 27 41 41 30 30 30 33 00 00 00 00 05 52 3A 00 00 00 7C 03 D1 42 42 30 30 30 33 43 43 43 43 30 33 
06 06 06 00 00 28 FF 7B 41 41 30 30 30 34 00 00 00 00 05 46 B1 00 00 00 73 01 10 42 42 30 30 30 34 43 43 30 30 30 34

## 索引IDX_C1叶子节点数据
06 06 20 00 10 00 00 42 42 30 30 30 31 41 41 30 30 30 31 
06 06 00 00 18 00 13 42 42 30 30 30 32 41 41 30 30 30 32 
06 06 00 00 20 00 13 42 42 30 30 30 33 41 41 30 30 30 33 
06 06 00 00 28 00 13 42 42 30 30 30 34 41 41 30 30 30 34 
06 06 00 00 30 FF A5 42 42 42 42 30 31 41 41 30 30 30 31

对比更新前后数据，发现：

1、更新未造成数据变化的操作不会导致主键记录的"事务信息“和"回滚指针"发生变化(需更多测试以确认)

2、当索引列被更新时，

未完待续

MySQL InnoDB Engine--数据页存储和DML操作

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