mybatise多层集合嵌套查询(3层)-蒲公英云

mybatise多层集合嵌套查询(3层)

1，用一个sql，多个resultMap 一般另起一个子map，不直接在collection中再套

每个子项都需要id才可避免子项自身被覆盖，永远1条

例如：

<select id="getSingleItemProductListForNew"  
        parameterType="com.mcd.cn.rdc.pcm.product.business.vo.template.TemplateParam"  
        resultMap="singleProductVOResultOnline">  
    SELECT  
    p.id,  
    p.CODE,  
    p.NAME,  
    p.long\_name,  
    p.description,  
    p.type,  
    p.sales\_flag,  
    p.ui\_type,  
    p.dayweek,  
    p.bu,  
    p.has\_grill,  
    p.daypart,  
    p.channel,  
    ttr.CODE tax\_rate\_type\_code,  
    ttr.tax\_rate,  
    tsp.start\_date,  
    tsp.end\_date,  
    tsd.start\_time,  
    tsd.end\_time,  
    le.content AS productLongNameEn,  
    tpg.id AS grill\_id,  
    tpg.grill\_code,  
    tpg.NAME AS grill\_name,  
    tpg.grill\_mode,  
    tpg.display\_mode,  
    tpg.quantity,  
    tpg.max\_quantity,  
    tpg.min\_quantity,  
    tpg.grill\_image,  
    tpgi.id grill\_item\_id,  
    tpgi.grill\_item\_code,  
    tpgi.NAME item\_name,  
    tpgi.quantity item\_quantity,  
    tpgi.is\_modify,  
    tpgi.grill\_item\_image,  
    tpgi.is\_default,  
    ttr1.CODE grill\_tax\_rate\_type\_code,  
    ttr1.tax\_rate grill\_tax\_rate  
    FROM  
    t\_product p  
    LEFT JOIN t\_product\_sales\_period tsp ON p.CODE = tsp.product\_code  
    AND p.data\_version = tsp.data\_version  
    LEFT JOIN t\_product\_sales\_daypart tsd ON p.CODE = tsd.product\_code  
    AND p.data\_version = tsd.data\_version  
    LEFT JOIN t\_product\_grill tpg ON tpg.product\_code = p.CODE  
    AND tpg.data\_version = p.data\_version  
    LEFT JOIN t\_product\_grill\_item tpgi ON tpg.data\_version = tpgi.data\_version  
    AND tpg.product\_code = tpgi.product\_code  
    AND tpg.grill\_code = tpgi.grill\_code  
    LEFT JOIN t\_master\_tax\_rate ttr1 ON tpg.tax\_rate\_type\_code = ttr1.  
    CODE LEFT JOIN t\_master\_tax\_rate ttr ON p.tax\_rate\_type\_code = ttr.  
    CODE LEFT JOIN t\_international\_language le ON le.key\_code = p.CODE  
    AND le.LANGUAGE = 'en\_US'  
    AND le.field\_name = 'productLongNameEn'  
    AND le.table\_name = 't\_product'  
    AND le.data\_version = p.data\_version  
    WHERE  
    p.\`status\` = '1'  
    AND p.data\_version = \#\{dataVersion\}  
    <if test="productCodes != null  and productCodes.size()>0">  
        AND p.code IN (  
        <foreach collection="productCodes" item="obj" index="index" separator=",">  
            \#\{obj\}  
        </foreach>  
        )  
    </if>  
</select>

2，用多个sql,第一个是主sql，其他是map嵌套sql
参看：
https://www.jianshu.com/p/80711449476c
https://www.cnblogs.com/hnsunlong/p/7195594.html
自动2层？

https://blog.csdn.net/u011006672/article/details/85258757?utm\_medium=distribute.pc\_aggpage\_search\_result.none-task-blog-2~all~first\_rank\_v2~rank\_v25-10-85258757.nonecase&utm\_term=mybatis%20%E5%A4%9A%E5%B1%82%E5%B5%8C%E5%A5%97%E6%9F%A5%E8%AF%A2