关联主表条件错误:多张表自连接无法正确拼出sql

bobo667 / mybatis-plus-join

mybatis-plus-join 多表插件完全按照mp的用法来做，你只要会mp，那你就会用mpj，无感引入，不会对之前的业务产生一点点影响，采用扩展方式来集成mp,更容易适配版本，后期mp版本升级，您不用更改东西，只需要更新版本就行，自定义返回Vo，自定义表别名，自定义查询字段，骚操作爽到爆，让你在喝有时间喝下午茶的时间，还能再吃点心（目前支持大部分主流版本）

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在commitid为bc76f750的提交中，已经存在过对此问题的修复，但是存在局限性。企业微信截图_e82f1d07-ac90-42af-9de3-d8174f142e7c

局限性为：仅解决了整个查询只有自连接的情况。举例：（这个sql是可以被正确拼接的）

SELECT
    c.* 
FROM
    cl_category c
    LEFT JOIN cl_category c2 ON c2.pid = c.id

以下这种情况的sql无法被正确拼接：期望：

SELECT
    goods.*,c.*
FROM
    goods goods
    LEFT JOIN category c ON c.id = goods.cid
    LEFT JOIN category c2 ON c2.id = c.pid
    LEFT JOIN category c3 ON c3.id = c2.cid
    LEFT JOIN category c4 ON c4.id = c3.pid

代码：

    JoinLambdaWrapper<Goods> queryWrapper = new JoinLambdaWrapper<>(ClGoods.class, "goods").selectAll()
                .leftJoin(Category.class, Category::getId, Goods::getCid, "c").selectAll().end()
                .leftJoin(Category.class, Category::getId, Category::getPid, "c2").end()
                .leftJoin(Category.class, Category::getId, Category::getPid, "c3").end()
                .leftJoin(Category.class, Category::getId, Category::getPid, "c4").end();

拼出来的sql为：

SELECT
    goods.*,c.*
FROM
    goods goods
    LEFT JOIN category c ON c.id = goods.cid
    LEFT JOIN category c2 ON c2.id = c2.pid
    LEFT JOIN category c3 ON c3.id = c3.pid
    LEFT JOIN category c4 ON c4.id = c4.pid

JoinLambdaWrapper<Goods> queryWrapper = new JoinLambdaWrapper<>(Goods.class, "goods").selectAll() .leftJoin(Category.class, Category::getId, Goods::getCid, "c").selectAll().end() .leftJoin(Category.class, Category::getId, Category::getPid, "c2", "c").end() .leftJoin(Category.class, Category::getId, Category::getPid, "c3", "c2").end() .leftJoin(Category.class, Category::getId, Category::getPid, "c4", "c3").end();

bobo667 / mybatis-plus-join

关联主表条件错误:多张表自连接无法正确拼出sql #8