基于seatunnel实现mysql同步clickhouse验证

场景：

需求想要实现mysql同步到clickhouse，seatunnel部署见前面文档linux环境seatunnel安装运行-CSDN博客。

官方说明文档

Clickhouse | Apache SeaTunnel

mysql同步配置

server-id=1
log_bin=/var/lib/mysql/bin.log
binlog_format=ROW
#binlog-do-db 具体要同步的数据库
binlog-do-db=gisqbpm
gtid-mode=on
enforce-gtid-consistency=on

验证MYSQL同步clckhouse

mysql数据库测试表

CREATE TABLE `test` (
`id_` varchar(255) NOT NULL,
`name` varchar(255) DEFAULT NULL,
PRIMARY KEY (`id_`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

clikhouse库测试表

-- gisqbpm.test definition

CREATE TABLE gisqbpm.test
(

`id_` String,

`name` Nullable(String),

`_sign` Int8 MATERIALIZED 1,

`_version` UInt64 MATERIALIZED 1,

INDEX _version _version TYPE minmax GRANULARITY 1
)
ENGINE = ReplacingMergeTree(_version)
ORDER BY tuple(id_)
SETTINGS index_granularity = 8192;

在config中创建mysqltoclickhouse.conf

touch mysqltoclickhouse.conf配置如下

env {
execution.parallelism = 1
job.mode = "STREAMING"
checkpoint.interval = 2000
}
source {
MySQL-CDC {
base-url = "jdbc:mysql://192.168.85.128:3307/gisqbpm"
username = "root"
password = "wxy123456"
table-names = ["gisqbpm.test"]
}
}

sink {
Clickhouse {
host = "192.168.85.128:8123"
database = "gisqbpm"
table = "test"
username = "default"
password = "wxy123456“
}
}

验证一：INSERT

mysql添加一条数据

INSERT INTO `gisqbpm`.`test`(`id_`, `name`) VALUES ('1', '李淳风');

select * from gisqbpm.test;

在clickhouse中也同步添加一条数据

验证二：UPDATE

mysql修改一条数据

update test set name='李淳风1' where id_='1';
select * from gisqbpm.test;

clickhouse显示如下，而是新增一个数据

验证三：DELETE

mysql删除一条数据

clickhouse发现是添加了一个数据

结论一：

这个是网上常见的案列，但都是往往写了一个添加操作就没了，奶奶个腿啊，这么多的坑竟然不说，妈的这放到生产环境不要气死人？同步时修改和删除变成添加和实际逻辑不一样。咨询了社区大佬，给我提供了一些意见，好吧那我就再验证一下

经过大佬点播，又看了一下官方文档确实有写，要通过主键去删除和更新！！！！

二：修改配置再次验证

env {
execution.parallelism = 1
job.mode = "STREAMING"
checkpoint.interval = 2000
}
source {
MySQL-CDC {
base-url = "jdbc:mysql://192.168.85.128:3307/gisqbpm"
username = "root"
password = "wxy123456"
table-names = ["gisqbpm.test"]
}
}

sink {
Clickhouse {
host = "192.168.85.128:8123"
database = "gisqbpm"
table = "test"
username = "default"
password = "wxy123456"
primary_key="id_"
support_upsert=true
}
}

验证一：INSERT

mysql插入一条数据

clickhouse也同步显示添加一条数据

验证二：DELETE

mysql删除一条数据

clickhouse也同步删除一条数据

验证三：UPDATE

mysql修改一条数据

clickhouse没有变化，服务此时也挂了

错误一：

错误如下 Caused by: org.apache.seatunnel.connectors.seatunnel.clickhouse.exception.ClickhouseConnectorException: ErrorCode:[COMMON-10], ErrorDescription:[Flush data operation that in sink connector failed] - Clickhouse execute batch statement error

重启后再次执行修改操作

mysql修改一条数据

clickhouse显示是新增一条数据

结论二：

这种方式同样也是不能完美解决同步问题，修改变成了添加，而且中途服务还挂了，稳定性也有风险。

三：修改配置再次验证

env {
execution.parallelism = 1
job.mode = "STREAMING"
checkpoint.interval = 2000
}
source {
MySQL-CDC {
base-url = "jdbc:mysql://192.168.85.128:3307/gisqbpm"
username = "root"
password = "wxy123456"
table-names = ["gisqbpm.test"]
}
}

sink {
Clickhouse {
host = "192.168.85.128:8123"
database = "gisqbpm"
table = "test"
username = "default"
password = "wxy123456"
primary_key="id_"
support_upsert=true
allow_experimental_lightweight_delete = true
}
}

这个是官方文档提供的配置测试一下

错误二：

Caused by: java.sql.BatchUpdateException: Code: 62. DB::Exception: Syntax error: failed at position 1 ('DELETE'): DELETE FROM "test" WHERE "id_" = '1' settings allow_experimental_lightweight_delete = true. Expected one of: Query, Query