子查询 1.5.2+

支持范围

• eq
• ne
• gt
• ge
• lt
• le
• in
• notIn
• exists
• notExists
• isNull
• isNotNull

API

以eq为例

/**
 * 参数说明
 *
 * @param colum eq对应的列
 * @param queryClass 子查询对应的主表类
 * @param wrapper 子查询构造器
 */
eq(SFunction colum, Class queryClass, Function wrapper);
/**
 * 条件重载 condition 为 false 时不添加条件
 */
eq(boolean condition, SFunction colum, Class queryClass, Function wrapper);

示例

以in为例

MPJLambdaWrapper<User> wrapper = JoinWrappers.lambda(User.class)
        .selectAll()
        .leftJoin(Address.class, Address::getUserId, User::getId)
        .in(User::getId, User.class, in -> in
                .select(User::getId)
                .between(User::getId, 0, 100));
wrapper.list();

对应sql

SELECT t.id,
       t.pid,
       t.`name`,
       t.`json`,
       t.sex,
       t.head_img,
       t.create_time
FROM `user` t
         LEFT JOIN address t1 ON (t1.user_id = t.id)
WHERE t.id IN (SELECT t.id FROM `user` t WHERE (t.id BETWEEN ? AND ?))

子查询别名

setAlias

MPJLambdaWrapper<User> wrapper = JoinWrappers.lambda(User.class)
        .selectAll()
        .leftJoin(Address.class, Address::getUserId, User::getId)
        .in(User::getId, User.class, in -> in
                .setAlias("sub") 
                .select(User::getId)
                .between(User::getId, 0, 100));
wrapper.list();

对应sql

SELECT t.id,
       t.pid,
       t.`name`,
       t.`json`,
       t.sex,
       t.head_img,
       t.create_time
FROM `user` t
         LEFT JOIN address t1 ON (t1.user_id = t.id)
WHERE t.id IN (SELECT sub.id FROM `user` sub WHERE sub.del = false AND (sub.id BETWEEN ? AND ?))

提示

过于复杂的需求或sql不推荐使用
不易维护，建议使用xml