mybatis plus 递归查询

MyBatis Plus doesn't provide built-in support for recursive querying. However, you can achieve recursive querying by leveraging the database's support for recursive queries or by writing custom SQL statements.

If your database supports recursive queries, you can use a common table expression (CTE) to perform the recursive query. Here's an example using PostgreSQL's recursive query syntax:

@Mapper
public interface MyMapper extends BaseMapper<MyEntity> {

    @Select("WITH RECURSIVE cte AS (" +
            "    SELECT * FROM my_table WHERE parent_id = #{parentId}" +
            "    UNION ALL" +
            "    SELECT t.* FROM my_table t JOIN cte ON t.parent_id = cte.id" +
            ")" +
            "SELECT * FROM cte")
    List<MyEntity> recursiveQuery(@Param("parentId") Long parentId);
}

In this example, `my_table` is the table you want to query recursively, and `parent_id` is the column that represents the parent-child relationship. The `recursiveQuery` method performs the recursive query and returns the results.

If your database doesn't support recursive queries, you can consider implementing a custom solution by fetching the initial records and recursively querying for their children until you reach the desired depth or condition. You can achieve this by writing custom SQL statements or by using a loop in your Java code.

Remember to adjust the SQL syntax according to your database's specific requirements and column names.