MySQL数据校验TIDB sync-diff-inspector

一、sync-diff-inspector简介

sync-diff-inspector 是由 PingCAP 开源的数据校验工具，用于校验MySQL/TiDB中两份数据是否一致。

主要功能如下：

对比表结构和数据

如果数据不一致，则生成用于修复数据的 SQL 语句

支持不同库名或表名的数据校验

支持分库分表场景下的数据校验

支持 TiDB 主从集群的数据校验

支持从 TiDB DM 拉取配置的数据校验

sync-diff-inspector 的使用限制

对于 MySQL 和 TiDB 之间的数据同步不支持在线校验，需要保证上下游校验的表中没有数据写入，或者保证某个范围内的数据不再变更.

FLOAT、DOUBLE 等浮点数类型在 TiDB 和 MySQL 中的实现方式不同，在计算 checksum 时会分别取 6 位和 15 位有效数字。如果不使用该特性，需要设置 ignore-columns 忽略这些列的检查。

支持对不包含主键或者唯一索引的表进行校验，但是如果数据不一致，生成的用于修复的 SQL 可能无法正确修复数据。

二、sync-diff-inspector工具下载安装

#sync-diff-inspector已集成在TiDB工具包中，直接下载TiDB工具包即可

wget https://download.pingcap.org/tidb-community-toolkit-v6.4.0-linux-amd64.tar.gz

tar zxvf tidb-community-toolkit-v6.4.0-linux-amd64.tar.gz

ls -lh tidb-community-toolkit-v6.4.0-linux-amd64 | grep sync_diff_inspector

-rwxr-xr-x 1 tidb tidb 98M Nov 17 11:41 sync_diff_inspector

./sync_diff_inspector -V

App Name: sync_diff_inspector v2.0

Release Version: v6.4.0

Git Commit Hash: f7e65073b35538def61ae094cd4a8e57e705344b

Git Branch: heads/refs/tags/v6.4.0

UTC Build Time: 2022-11-04 07:21:08

Go Version: go1.19.2

三、sync-diff-inspector工具使用示例

1.配置文件通用部分

cat config.toml

check-thread-count = 4 # 检查数据的线程数量

export-fix-sql = true # 如果开启，若表数据存在不一致，则输出用于修复的SQL语句

check-struct-only = false # 只对比表结构而不对比数据

[data-sources]

[data-sources.mysql1] # 上游MySQL数据库配置（源端）

host = "10.186.65.57"

port = 3306

user = "sgy"

password = "admin"

route-rules = ["rule1"] # 映射匹配规则,通过配置相应的规则可以对单个、多个schema或table进行校验

# 如有多个rule时，可配置成 ["rule1", "rule2"]

[data-sources.mysql2] # 下游MySQL数据库配置（目标端）

host = "10.186.65.89"

port = 3309

user = "sgy"

password = "admin"

2.基于schema的数据校验

对单个schema进行数据校验

#映射匹配规则部分,需要将此部分放到置配置文件通用部分的后面

[routes] # 映射关系,如上下游schema不同名可在此配置

[routes.rule1]

schema-pattern = "sbtest" # 匹配上游数据库的的库名

target-schema = "sbtest" # 匹配下游数据库的库名

[task]

output-dir = "./output"

source-instances = ["mysql1"] # 上游数据库，内容是 data-sources 声明的唯一标识 id，分库分表场景下支持多个上游数据库，如：["mysql10", "mysql20"]

target-instance = "mysql2" # 下游数据库，内容是 data-sources 声明的唯一标识 id

target-check-tables = ["sbtest.*"] # 需要比对的下游数据库的表

# 进行数据校验

./sync_diff_inspector --config=./config.toml

A total of 8 tables need to be compared

Progress [>------------------------------------------------------------] 0% 0/0

Comparing the table structure of ``sbtest`.`sbtest4`` ... equivalent #表结构一致

Comparing the table structure of ``sbtest`.`sbtest5`` ... equivalent

.......................................................

Comparing the table data of ``sbtest`.`sbtest2`` ... equivalent #表中数据一致

Comparing the table data of ``sbtest`.`sbtest8`` ... equivalent

_____________________________________________________________________________

Progress [============================================================>] 100% 0/0

A total of 8 table have been compared and all are equal.

You can view the comparision details through './output/sync_diff.log'

对多个schema进行数据校验

#由于对多个schema进行数据校验，routes包含了rule1、rule2,配置文件通用部分需要做以下修改

[data-sources.mysql1]

route-rules = ["rule1","rule2"]

#映射匹配规则部分,需要将此部分放到配置文件通用部分的后面

[routes]

[routes.rule1]

schema-pattern = "sbtest*" #使用正则匹配sbtest开头的schema，如sbtest,sbtest1,sbtest2,sbtest3

target-schema = "sbtest*"

[routes.rule2]

schema-pattern = "sgy" #匹配schema:sgy

target-schema = "sgy"

[task]

output-dir = "./output"

source-instances = ["mysql1"] # 上游数据库，内容是 data-sources 声明的唯一标识.

target-instance = "mysql2" # 下游数据库，内容是 data-sources 声明的唯一标识 id

target-check-tables = [ "sbtest*.*","sgy.*"] #对源、目标实例中的sgy及以sbtest开头的schema所有表进行校验

#进行数据校验

./sync_diff_inspector --config=./config.toml

A total of 24 tables need to be compared

Progress [>------------------------------------------------------------] 0% 0/0

Comparing the table structure of ``sgy`.`sbtest2`` ... equivalent

Comparing the table data of ``sgy`.`sbtest2`` ... equivalent

.......................................................

Comparing the table data of ``sbtest`.`sbtest1`` ... equivalent

Comparing the table data of ``sbtest3`.`sbtest1`` ... equivalent

Comparing the table data of ``sbtest2`.`sbtest1`` ... equivalent

Comparing the table data of ``sbtest1`.`sbtest2`` ... equivalent

_____________________________________________________________________________

Progress [============================================================>] 100% 0/0

A total of 24 table have been compared and all are equal.

You can view the comparision details through './output/sync_diff.log'

3.基于table的数据校验

对单个table进行数据校验

#映射匹配规则部分,需要将此部分放置到配置文件通用部分的后面

[routes]

[routes.rule1]

schema-pattern = "sbtest"

target-schema = "sbtest"

[task]

output-dir = "./output"

source-instances = ["mysql1"] # 上游数据库，内容是 data-sources 声明的唯一标识

target-instance = "mysql2" # 下游数据库，内容是 data-sources 声明的唯一标识 id

target-check-tables = ["sbtest.sbtest1"] #只校验表： sbtest.sbtest1

#进行数据校验

./sync_diff_inspector --config=./config.toml

A total of 1 tables need to be compared

Progress [>------------------------------------------------------------] 0% 0/0

Comparing the table structure of ``sbtest`.`sbtest1`` ... equivalent

Comparing the table data of ``sbtest`.`sbtest1`` ... equivalent

_____________________________________________________________________________

Progress [============================================================>] 100% 0/0

A total of 1 table have been compared and all are equal.

You can view the comparision details through './output/sync_diff.log'

对多个table进行数据校验

#对schema进行数据校验也是对多个table进行数据校验的一种，这里以指定多个具体表名为例

#由于对多个table进行数据校验，routes包含了rule1、rule2,配置文件通用部分需要做以下修改

[data-sources.mysql1]

route-rules = ["rule1","rule2"]

#映射匹配规则部分,需要将此部分放置到配置文件通用部分的后面

[routes]

[routes.rule1]

schema-pattern = "sbtest*"

target-schema = "sbtest*"

[routes.rule2]

schema-pattern = "sgy"

target-schema = "sgy"

[task]

output-dir = "./output"

source-instances = ["mysql1"] # 上游数据库，内容是 data-sources 声明的唯一标识

target-instance = "mysql2" # 下游数据库，内容是 data-sources 声明的唯一标识 id

#只校验sbtest.sbtest8,sgy.sbtest4,sbtest1.sbtest1,sbtest2.sbtest2这四个表

target-check-tables = [ "sbtest.sbtest8","sgy.sbtest4","sbtest1.sbtest1","sbtest2.sbtest2"]

#进行数据校验

./sync_diff_inspector --config=./config.toml

A total of 4 tables need to be compared

Progress [>------------------------------------------------------------] 0% 0/0

Comparing the table structure of ``sbtest2`.`sbtest2`` ... equivalent

Comparing the table data of ``sbtest2`.`sbtest2`` ... equivalent

Comparing the table structure of ``sgy`.`sbtest4`` ... equivalent

Comparing the table structure of ``sbtest1`.`sbtest1`` ... equivalent

Comparing the table data of ``sgy`.`sbtest4`` ... equivalent

Comparing the table data of ``sbtest1`.`sbtest1`` ... equivalent

Comparing the table structure of ``sbtest`.`sbtest8`` ... equivalent

Comparing the table data of ``sbtest`.`sbtest8`` ... equivalent

_____________________________________________________________________________

Progress [============================================================>] 100% 0/0

A total of 4 table have been compared and all are equal.

You can view the comparision details through './output/sync_diff.log'

对单表进行范围校验

#映射匹配规则部分,需要将此部分放置到配置文件通用部分的后面

[routes]

[routes.rule1]

schema-pattern = "sbtest"

target-schema = "sbtest"

[task]

output-dir = "./output"

source-instances = ["mysql1"] # 上游数据库，内容是 data-sources 声明的唯一标识

target-instance = "mysql2" # 下游数据库，内容是 data-sources 声明的唯一标识 id

target-check-tables = ["sbtest.sbtest1"] # 指定校验目标实例上的sbtest.sbtest1表

target-configs = ["config1"] # 对部分表的额外配置

[table-configs.config1]

target-tables = ["sbtest.sbtest1"] # 指定校验目标实例上的sbtest.sbtest1表

range = "id > 10 AND id < 100" # 指定校验目标表的具体范围，相当于SQL中的where条件

#数据校验见数据修复功能部分

4.数据修复功能

#为了演示数据修复，在目标端表中删除一些数据

mysql -usgy -padmin -h 10.186.65.89 -P 3309 -e "delete from sbtest.sbtest1 where id in (11,22,33,44,55,66,77,88,99);"

# 使用对单表进行范围校验配置，对sbtest.sbtest1表进行范围校验

./sync_diff_inspector --config=./config.toml

A total of 1 tables need to be compared

Comparing the table structure of ``sbtest`.`sbtest1`` ... equivalent #sbtest.sbtest1表结构一致

Comparing the table data of ``sbtest`.`sbtest1`` ... failure #sbtest.sbtest1表数据有差异

_____________________________________________________________________________

Progress [============================================================>] 100% 0/0

The data of `sbtest`.`sbtest1` is not equal

The rest of tables are all equal.

The patch file has been generated in

'output/fix-on-mysql2/' # 生成修复SQL输出到此目录

You can view the comparision details through './output/sync_diff.log'

# 查看输出修复SQL

cat output/fix-on-mysql2/sbtest\:sbtest1\:0\:0-0\:0.sql

-- table: sbtest.sbtest1

-- range in sequence: Full

REPLACE INTO `sbtest`.`sbtest1`(`id`,`k`,`c`,`pad`) VALUES (11,50148,'69183965773-14680923687-92934799461-07606242492-78811530738-23241332728-92911647895-70477201282-85254929997-06214236905','33737501839-63208420999-35708593012-95906952636-68691055996');

REPLACE INTO `sbtest`.`sbtest1`(`id`,`k`,`c`,`pad`) VALUES (22,41538,'14140185946-16271766410-68340573738-46226480462-08989140676-29936780681-56784925909-45742390296-67137862436-18242076592','25112986220-19824650341-42825248958-70186905082-33867163574');

REPLACE INTO `sbtest`.`sbtest1`(`id`,`k`,`c`,`pad`) VALUES (33,50105,'48402160130-78797253227-05588677001-93556313541-39295466587-91364622063-58862572731-27837539373-64526858273-89372384747','72073637794-12055602042-16862397531-87496431032-85451396141');

REPLACE INTO `sbtest`.`sbtest1`(`id`,`k`,`c`,`pad`) VALUES (44,49917,'98096713237-15265478716-72025332919-62964308854-01270604715-12000922788-50929365082-43513513022-28543412388-57790852446','33907865533-62267179125-36062850111-84091551774-69847376840');

REPLACE INTO `sbtest`.`sbtest1`(`id`,`k`,`c`,`pad`) VALUES (55,50259,'68826640374-18002055907-53999869701-72145793168-90893177888-85273641163-24331745145-62755454379-79511152711-99618812770','02724012569-91405199011-30257626349-21678066897-42535351703');

REPLACE INTO `sbtest`.`sbtest1`(`id`,`k`,`c`,`pad`) VALUES (66,41995,'58396552954-26907336026-99506693837-77815822050-42927030403-40927779227-58101279219-11438233008-00344004393-35806649113','02348992414-65327666387-20632806790-74456238429-90933031209');

REPLACE INTO `sbtest`.`sbtest1`(`id`,`k`,`c`,`pad`) VALUES (77,49757,'73705207329-00308504929-05904865650-29498186065-09990420614-84131302024-40320022420-77358683577-34731688411-70665402097','92567035674-84728177369-79087155038-84461952379-45481760225');

REPLACE INTO `sbtest`.`sbtest1`(`id`,`k`,`c`,`pad`) VALUES (88,50497,'77112982215-98755241853-36424062009-45217742824-83650985380-60232607362-47569976121-30091332050-97996374956-97911403909','88977046077-43519705750-51246090615-77629911610-94055348738');

REPLACE INTO `sbtest`.`sbtest1`(`id`,`k`,`c`,`pad`) VALUES (99,49977,'63255973711-62890656114-72914458941-22277906368-32619356110-31219579310-16762665782-69578495131-76043317830-28240408380','08589883275-03392784968-00244590156-39735355951-95769933801');

#将生成的修复SQL导入目标库

mysql -usgy -padmin -h 10.186.65.89 -P 3309 < output/fix-on-mysql2/sbtest\:sbtest1\:0\:0-0\:0.sql

mysql: [Warning] Using a password on the command line interface can be insecure.

#再次检验,发现数据已经一致

./sync_diff_inspector --config=./config.toml

A total of 1 tables need to be compared

Comparing the table structure of ``sbtest`.`sbtest1`` ... equivalent

Comparing the table data of ``sbtest`.`sbtest1`` ... equivalent

_____________________________________________________________________________

Progress [============================================================>] 100% 0/0

A total of 1 table have been compared and all are equal.

You can view the comparision details through './output/sync_diff.log'

四、相关问题

修改配置文件后需要手动删除outputDir目录

vim config.toml

./sync_diff_inspector --config=./config.toml #将output-dir删除即可解决

Fail to initialize config.

failed to init Task: config changes breaking the checkpoint, please use another outputDir and start over again!

表建议使用utf8mb4字符集，不支持MySQL8.0的utf8mb3字符集

mysql> select @@version;

+-----------+

| @@version |

+-----------+

| 8.0.30 |

+-----------+

1 row in set (0.00 sec)

mysql> alter table sgy.sbtest4 CHARSET=utf8;

Query OK, 0 rows affected, 1 warning (0.01 sec)

Records: 0 Duplicates: 0 Warnings: 1

mysql> show create table sgy.sbtest4 \G

*************************** 1. row ***************************

Table: sbtest4

Create Table: CREATE TABLE `sbtest4` (

`id` int NOT NULL AUTO_INCREMENT,

`k` int NOT NULL DEFAULT '0',

`c` char(120) CHARACTER SET utf8mb4 COLLATE utf8mb4_bin NOT NULL DEFAULT '',

`pad` char(60) CHARACTER SET utf8mb4 COLLATE utf8mb4_bin NOT NULL DEFAULT '',

PRIMARY KEY (`id`),

KEY `k_4` (`k`)

) ENGINE=InnoDB AUTO_INCREMENT=100001 DEFAULT CHARSET=utf8mb3

1 row in set (0.00 sec)

#执行数据校验时报错

./sync_diff_inspector --config=./config.toml

There is something error when initialize diff, please check log info in output/sync_diff.log

#查看日志文件

cat output/sync_diff.log |grep utf8mb3

[2023/02/19 11:13:04.980 +08:00] [FATAL] [main.go:120] ["failed to initialize diff process"] [error="get table sgy.sbtest4's information error [parser:1115]Unknown character set: 'utf8mb3'\ngithub.com/pingcap/errors.

更详细的使用说明，请参考官方文档：https://docs.pingcap.com/zh/tidb/stable/sync-diff-inspector-overview