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  • 05mycat父子表

    表连接的难题在mycat中是不允许跨分片做表连接查询的

    创建t_orders表

    create table t_orders(

    id int PRIMARY key,

    customer_id int not null,

    datetime TIMESTAMP DEFAULT CURRENT_TIMESTAMP

    );

    #################################################

    use chinasoft;

    create table t_customer(

    id int primary key,

    username varchar(200) not null,

    sharding_id int not null

    );

    use chinasoft;

    select * from t_customer;

    insert into t_customer(id,username,sharding_id) values(1,"tom",101);

    insert into t_customer(id,username,sharding_id) values(2,"jack",102);

    insert into t_customer(id,username,sharding_id) values(3,"smith",105);

    insert into t_customer(id,username,sharding_id) values(4,"lily",102);

    insert into t_customer(id,username,sharding_id) values(5,"lucy",103);

    insert into t_customer(id,username,sharding_id) values(6,"hanmeimei",104);

    create table t_orders(

    id int PRIMARY key,

    customer_id int not null,

    datetime TIMESTAMP DEFAULT CURRENT_TIMESTAMP

    );

    INSERT into t_orders(id,customer_id) values(1,1);

    INSERT into t_orders(id,customer_id) values(2,1);

    INSERT into t_orders(id,customer_id) values(3,1);

    select c.username,o.id,o.datetime from t_customer c join t_orders o on c.id=o.customer_id;

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  • 原文地址:https://www.cnblogs.com/reblue520/p/10338537.html
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