详细的编译方法,详见。
分表(partition)版配置文件基本跟分片(shard)版本一样,不同之处在shard.conf文件:
- 配置partition-mode=true, 使cetus工作在分表模式
- proxy-backend-addresses和proxy-read-only-backend-addresses配置具体参考读写分离,不需要像分库那样加group
- 子表名的约定
例如,配置文件sharding.json中配置如下:
{
"id": 1,
"type": "int",
"method": "hash",
"num": 4,
"partitions": {"data1": [0,1], "data2": [2,3]}
}],
"table": [
{"vdb": 1, "db": "ght", "table": "t1", "pkey": "id"}
]
}
则表t1分2个子表,分表之后的各个子表名为:t1_data1, t1_data2。
- 子表的创建
假设,目前需要将表tb,按照hash方式分成4个子表,每个子表表名分别为:tb_hs0, tb_hs1, tb_hs2, tb_hs3。则实现上述需求,配置步骤如下:
- 编译shard版本的Cetus,参考编译命令如下:
proxy-backend-addresses=172.17.0.3:3306
proxy-read-only-backend-addresses=172.17.0.4:3306
partition-mode=true
特别注意, 不需要在IP PORT后添加@data1
- 配置sharding.json,配置分表规则
- 创建子表
use ght;
create table tb_hs1 (id int);
create table tb_hs2 (id int);
create table tb_hs3 (id int);
- 启动Cetus
- 验证
登录Cetus的代理端口,执行shard_explain
命令,查看路由情况:
shard_explain select * from tb where id = 7;
+--------+-------------------------------------+
| groups | sql |
+--------+-------------------------------------+
| hs3 | SELECT * FROM tb_hs3 WHERE id = 7; |
+--------+-------------------------------------+
1 row in set (0.00 sec)
shard_explain select * from tb where id = 5;
| groups | sql |
+--------+-------------------------------------+
+--------+-------------------------------------+
1 row in set (0.00 sec)
shard_explain select * from tb where id = 3;
+--------+-------------------------------------+
| groups | sql |
+--------+-------------------------------------+
| hs1 | SELECT * FROM tb_hs1 WHERE id = 3; |
+--------+-------------------------------------+
1 row in set (0.00 sec)
shard_explain select * from tb where id = 1;
+--------+-------------------------------------+
| groups | sql |
+--------+-------------------------------------+
| hs0 | SELECT * FROM tb_hs0 WHERE id = 1; |
1 row in set (0.00 sec)