mysql 一个update语句 对主表内容和子表批量修改
2024-05-06 12:48:06
1.
(附加内容：什么时候复写equals和hashCode，为什么有的人不喜欢用lombock)
在开发中，经常会遇到 修改一张主表的数据后，然后再去修改字表的内容，一般是调用两个sql
下面的例子完成 单条sql 完成 主表和字表的批量修改（如果子表涉及到新增，就需要insert语句，这里暂不讨论）
1. 批量修改的语法
update ( A inner |left | right join on B on A.id = B表.A_id)
set A.字段1 = "新值" ,
A.字段2 = "新值" ,
B.字段1 = "新值" ,
B.字段2 = "新值"
where 过滤条件;
说明： 是把红色标出来的结果集当成一张表处理的
单表修改语句语法：
UPDATE 表名称 SET 列名称 = 新值 WHERE 列名称 = 某值举例说明：
两张表一对多 :
commodity_order , commodity_order_detail表里数据如下：
select * from commodity_order;+--+----+---------+---------+
|id|name|custom_id|is_delete|
+--+----+---------+---------+
|1 |置办年货|1 |0 |
|2 |买衣服 |1 |0 |
+--+----+---------+---------+
select * from commodity_order_detail;+--+--------+--------------+------------+---------------+---------+
|id|order_id|commodity_name|commodity_id|commodity_count|is_delete|
+--+--------+--------------+------------+---------------+---------+
|1 |1 |鞭炮 |1 |1 |0 |
|2 |1 |春联 |2 |1 |0 |
|3 |1 |牛丸 |3 |1 |0 |
|4 |2 |冬装 |4 |1 |0 |
|5 |2 |夏装 |5 |1 |0 |
+--+--------+--------------+------------+---------------+---------+以下为练习：
select * from commodity_order;
select * from commodity_order_detail;
#
select 1 as A,2 as B;
# +-+-+
# |A|B|
# +-+-+
# |1|2|
# +-+-+# 列转行(一行成多行)SQL：
select 1
union select 2;# 先建表
# create table sql_test.commodity_order
# (
# id int auto_increment
# primary key,
# name varchar(20) null,
# custom_id varchar(20) null,
# is_delete int null
# )
# comment '订单主表';
# create table sql_test.commodity_order_detail
# (
# id int auto_increment
# primary key,
# order_id int null,
# commodity_name varchar(20) null,
# commodity_id int null,
# commodity_count int null,
# is_delete int null
# )
# comment '订单明细表';select * from commodity_order;
# +--+----+---------+
# |id|name|custom_id|
# +--+----+---------+
# |1 |置办年货|1 |
# +--+----+---------+select * from commodity_order_detail;
# +--+--------+--------------+------------+---------------+
# |id|order_id|commodity_name|commodity_id|commodity_count|
# +--+--------+--------------+------------+---------------+
# |1 |1 |鞭炮 |1 |1 |
# |2 |1 |春联 |2 |2 |
# |3 |1 |牛丸 |3 |3 |
# +--+--------+--------------+------------+---------------+
# 表名不可以是关键字 order
select o.* ,d.*
from commodity_order oinner join commodity_order_detail d on o.id = d.order_id and d.is_delete = 0
where o.id = 1 and o.is_delete = 0;
# +--+----+---------+---------+--+--------+--------------+------------+---------------+---------+
# |id|name|custom_id|is_delete|id|order_id|commodity_name|commodity_id|commodity_count|is_delete|
# +--+----+---------+---------+--+--------+--------------+------------+---------------+---------+
# |1 |置办年货|1 |0 |1 |1 |鞭炮 |1 |1 |0 |
# |1 |置办年货|1 |0 |2 |1 |春联 |2 |2 |0 |
# |1 |置办年货|1 |0 |3 |1 |牛丸 |3 |3 |0 |
# +--+----+---------+---------+--+--------+--------------+------------+---------------+---------+#（修改的批量操作） 需求1：用户做编辑操作，删掉了鞭炮和牛丸 (前段会传 订单明细id 1和 2)
# 先获取要处理的数据集（交集），此处是对订单明细 1和 2 的数据做处理
# update commodity_order_detail set is_delete = 1 where id in (1,2) 这个sql可以解决，但为了引出批量操作的sql 这里引出另一种思路
# 下面的sql写的有点麻烦了，优化后的sql如下select *
from (select 1 As detail_idunionselect 2 as detail_id) tmp_detailinner join commodity_order_detail detail on tmp_detail.detail_id = detail.id and detail.is_delete = 0 ;
# +---------+--+--------+--------------+------------+---------------+---------+
# |detail_id|id|order_id|commodity_name|commodity_id|commodity_count|is_delete|
# +---------+--+--------+--------------+------------+---------------+---------+
# |1 |1 |1 |鞭炮 |1 |1 |0 |
# |2 |2 |1 |春联 |2 |2 |0 |
# +---------+--+--------+--------------+------------+---------------+---------+
# 优化后的sql
select * from commodity_order_detail detail detail.id in (1,2) and detail.is_delete = 0 ;# 获取到要操作的数据集后 ，将结果看成一张表
# update 虚拟表 set 字段 = 值 where 过滤条件update (
# 上面获取结果集只要from 后面的(select 1 As detail_idunionselect 2 as detail_id) tmp_detailinner join commodity_order_detail detail on tmp_detail.detail_id = detail.id and detail.is_delete = 0) set detail.is_delete = 1 where detail.order_id = 1;优化后的sql如下：
update (
# 上面获取结果集只要from 后面的commodity_order_detail detail detail.id in (1,2) and detail.is_delete = 0) set detail.is_delete = 1 where detail.order_id = 1;
# 查看结果 发现数据修改成功
select * from commodity_order_detail;
# +--+--------+--------------+------------+---------------+---------+
# |id|order_id|commodity_name|commodity_id|commodity_count|is_delete|
# +--+--------+--------------+------------+---------------+---------+
# |1 |1 |鞭炮 |1 |1 |1 |
# |2 |1 |春联 |2 |2 |1 |
# |3 |1 |牛丸 |3 |3 |0 |
# +--+--------+--------------+------------+---------------+---------+# 修改主表的name和逻辑删除 一个sql处理
# 先获取要操作的数据集
select * from((select 1 As detail_idunionselect 2 as detail_id) tmp_detailinner join commodity_order_detail detail on tmp_detail.detail_id = detail.id and detail.is_delete = 0inner join commodity_order co on detail.is_delete = co.is_delete and co.id = detail.order_id) ;
# +---------+--+--------+--------------+------------+---------------+---------+--+----+---------+---------+
# |detail_id|id|order_id|commodity_name|commodity_id|commodity_count|is_delete|id|name|custom_id|is_delete|
# +---------+--+--------+--------------+------------+---------------+---------+--+----+---------+---------+
# |1 |1 |1 |鞭炮 |1 |1 |0 |1 |置办年货|1 |0 |
# |2 |2 |1 |春联 |2 |2 |0 |1 |置办年货|1 |0 |
# +---------+--+--------+--------------+------------+---------------+---------+--+----+---------+---------+优化后的sql：
select * from commodity_order corder inner join commodity_order_detail detail on corder .id =detail.order_id and detail.is_delete = 0 and corder.is_delete = 0 # 执行sql进行多表的修改
①
update (
# 上面获取结果集只要from 后面的(select 1 As detail_idunionselect 2 as detail_id) tmp_detailinner join commodity_order_detail detail on tmp_detail.detail_id = detail.id and detail.is_delete = 0inner join commodity_order co on detail.is_delete = co.is_delete and co.id = detail.order_id)
# 修改主表数据
set co.name = '第二次置办年货',
# 修改字表数据
detail.is_delete = 1
where detail.order_id = 1;② 优化后sql
update (
# 上面获取结果集只要from 后面的commodity_order corder inner join commodity_order_detail detail on corder .id =detail.order_id and detail.is_delete = 0 and corder.is_delete = 0)
# 修改主表数据
set co.name = '第二次置办年货',
# 修改明细字段数据
detail.is_delete = 1
where detail.order_id = 1;# 查看修改后的数据 ，操作成功
select o.* ,d.*
from commodity_order oinner join commodity_order_detail d on o.id = d.order_id and d.is_delete = 0
where o.id = 1 and o.is_delete = 0;# +--+-------+---------+---------+--+--------+--------------+------------+---------------+---------+
# |id|name |custom_id|is_delete|id|order_id|commodity_name|commodity_id|commodity_count|is_delete|
# +--+-------+---------+---------+--+--------+--------------+------------+---------------+---------+
# |1 |第二次置办年货|1 |0 |3 |1 |牛丸 |3 |3 |0 |
# +--+-------+---------+---------+--+--------+--------------+------------+---------------+---------+# 需求二：将主订单名字改为 第二次置办年货 ，
# 将订单明细名字鞭炮和牛丸的数量分别改成50，100,名字分别改成 第二次鞭炮,第二次牛丸
# 订单明细中 春联数据不动
# （在将原来数据还原的基础上进行的）
# 前段传 订单明细表id ，修改后的名称和数量 ，转成sql如下
select '1' detail_id ,'第二次鞭炮' as commodity_name ,'50' as commodity_count
union select '3' detail_id ,'第二次牛丸' as commodity_name ,'100' as commodity_count;
# +---------+--------------+---------------+
# |detail_id|commodity_name|commodity_count|
# +---------+--------------+---------------+
# |1 |第二次鞭炮 |50 |
# |3 |第二次牛丸 |100 |
# +---------+--------------+---------------+
# 上述表和主订单，订单明细关联后获取的数据
select *
from ((select '1' detail_id, '第二次鞭炮' as tem_commodity_name, '50' as commodity_countunionselect '3' detail_id, '第二次牛丸' as tmp_commodity_name, '100' as commodity_count) as tmpinner join commodity_order_detail d on d.id = tmp.detail_id and d.is_delete = 0inner join commodity_order o on o.id = d.order_id and o.is_delete = d.is_delete
# 这是后台传进来的 主订单id ，不能写死 ，这儿加 o.id = 1 是为了获取更少的数据集and o.id = 1);
# +---------+------------------+---------------+--+--------+--------------+------------+---------------+---------+--+----+---------+---------+
# |detail_id|tem_commodity_name|commodity_count|id|order_id|commodity_name|commodity_id|commodity_count|is_delete|id|name|custom_id|is_delete|
# +---------+------------------+---------------+--+--------+--------------+------------+---------------+---------+--+----+---------+---------+
# |1 |第二次鞭炮 |50 |1 |1 |鞭炮 |1 |1 |0 |1 |置办年货|1 |0 |
# |3 |第二次牛丸 |100 |3 |1 |牛丸 |3 |3 |0 |1 |置办年货|1 |0 |
# +---------+------------------+---------------+--+--------+--------------+------------+---------------+---------+--+----+---------+---------+
# 加个套形成update语句，执行
update (
# 操作的数据集start(select '1' detail_id, '第二次鞭炮' as tmp_commodity_name, '50' as tmp_commodity_countunionselect '3' detail_id, '第二次牛丸' as tmp_commodity_name, '100' as tmp_commodity_count) as tmpinner join commodity_order_detail d on d.id = tmp.detail_id and d.is_delete = 0inner join commodity_order o on o.id = d.order_id and o.is_delete = d.is_delete
# 这是后台传进来的 主订单id ，不能写死 ，这儿加 o.id = 1 是为了获取更少的数据集and o.id = 1
# 操作的数据集end)
# 将 前段传过来的 tem 里的 字段值 赋值给 物理表
set o.name = '第二次置办年货',d.commodity_name = tmp.tmp_commodity_name,d.commodity_count = tmp.tmp_commodity_count
# o.id = 1 加到这里也行
where o.id = 1 ;
# 修改后查询 主表和字表数据
# +--+-------+---------+---------+--+--------+--------------+------------+---------------+---------+
# |id|name |custom_id|is_delete|id|order_id|commodity_name|commodity_id|commodity_count|is_delete|
# +--+-------+---------+---------+--+--------+--------------+------------+---------------+---------+
# |1 |第二次置办年货|1 |0 |1 |1 |第二次鞭炮 |1 |50 |0 |
# |1 |第二次置办年货|1 |0 |2 |1 |春联 |2 |2 |0 |
# |1 |第二次置办年货|1 |0 |3 |1 |第二次牛丸 |3 |100 |0 |
# +--+-------+---------+---------+--+--------+--------------+------------+---------------+---------+# 需求三：将主订单名字改为 第二次置办年货 ， (还是一个sql完成)
# 将订单明细名字鞭炮和牛丸的数量分别改成50，100,名字分别改成 第二次鞭炮,第二次牛丸
# 订单明细中 春联数据逻辑删除
# （在将原来数据还原的基础上进行的）
# 需求分析：获取操作的数据集（取两张表的交集），对交集处理，
# -------> 需求转换：因为 前段传输给的 名字鞭炮和牛丸 这是个对象，是集合List A 的元素，后台我拿出主订单下id 为 1 的所有子订单 B，取出B的差集removeAll or filter 筛选出要
# 要删除的元素，形成一个新的要删除订单明细的集合C，A和C 这两个集合合并，就是要逻辑处理的 记录，这样删除的时候也不会，将要删除记录的其他字段设置为 ‘’
# java代码实现# 需求四：将主订单名字改为 第二次置办年货 ，（两条sql = 批量新增的sql+批量修改的sql）
# 将订单明细名字 新增一条数据 需要用insert语句
# 将订单明细名字鞭炮和牛丸的数量分别改成50，100,名字分别改成 第二次鞭炮,第二次牛丸 update 语句批量修改
# 订单明细中 春联数据逻辑删除 update 语句批量修改
# （在将原来数据还原的基础上进行的）2.java实现(一个简单的springboot项目)
这篇文章写的也挺不错的
https://blog.csdn.net/lan_qinger/article/details/84138216
先展示效果，然后代码
根据订单id 查出的json效果：
{"id": 1,"name": "置办年货","isDelete": 0,"detailsList": [{"id": 1,"orderId": "1","commodityName": "鞭炮","commodityId": "1","commodityCount": 1,"isDelete": 0},{"id": 2,"orderId": "1","commodityName": "春联","commodityId": "2","commodityCount": 1,"isDelete": 0},{"id": 3,"orderId": "1","commodityName": "牛","commodityId": "3","commodityCount": 1,"isDelete": 0}]
}① 批量增加两条数据
入参：
{"id": 1,"name": "置办年货","isDelete": 0,"detailsList": [{"id": 1,"orderId": "1","commodityName": "鞭炮(edit name)","commodityId": "1","commodityCount": 1,"isDelete": 0},{"id": 2,"orderId": "1","commodityName": "春联(edit count)","commodityId": "2","commodityCount": 100,"isDelete": 0},{"id": 3,"orderId": "1","commodityName": "牛","commodityId": "3","commodityCount": 1,"isDelete": 0},{"orderId": "1","commodityName": "新增1","commodityId": "4","commodityCount": 1,"isDelete": 0},{"orderId": "1","commodityName": "新增2","commodityId": "5","commodityCount": 1,"isDelete": 0}]
}出参：
{"id": 1,"name": "置办年货","isDelete": 0,"detailsList": [{"id": 1,"orderId": 1,"commodityName": "鞭炮(edit name)","commodityId": "1","commodityCount": 1,"isDelete": 0},{"id": 2,"orderId": 1,"commodityName": "春联(edit count)","commodityId": "2","commodityCount": 100,"isDelete": 0},{"id": 3,"orderId": 1,"commodityName": "牛","commodityId": "3","commodityCount": 1,"isDelete": 0},{"id": 14,"orderId": 1,"commodityName": "新增1","commodityId": "4","commodityCount": 1,"isDelete": 0},{"id": 15,"orderId": 1,"commodityName": "新增2","commodityId": "5","commodityCount": 1,"isDelete": 0}]
}② 批量删除两条
入参：
{"id": 1,"name": "置办年货","isDelete": 0,"detailsList": [{"id": 1,"orderId": "1","commodityName": "鞭炮(edit name)","commodityId": "1","commodityCount": 1,"isDelete": 0}]
}出参：
{"id": 1,"name": "置办年货","isDelete": 0,"detailsList": [{"id": 1,"orderId": 1,"commodityName": "鞭炮(edit name)","commodityId": "1","commodityCount": 1,"isDelete": 0}]
}③ 逻辑编辑两条
入参：
{"id": 1,"name": "置办年货","isDelete": 0,"detailsList": [{"id": 1,"orderId": "1","commodityName": "鞭炮(edit name)","commodityId": "1","commodityCount": 1,"isDelete": 0},{"id": 2,"orderId": "1","commodityName": "春联(edit count)","commodityId": "2","commodityCount": 100,"isDelete": 0},{"id": 3,"orderId": "1","commodityName": "牛","commodityId": "3","commodityCount": 1,"isDelete": 0}]
}出参：
{"id": 1,"name": "置办年货","isDelete": 0,"detailsList": [{"id": 1,"orderId": 1,"commodityName": "鞭炮(edit name)","commodityId": "1","commodityCount": 1,"isDelete": 0},{"id": 2,"orderId": 1,"commodityName": "春联(edit count)","commodityId": "2","commodityCount": 100,"isDelete": 0},{"id": 3,"orderId": 1,"commodityName": "牛","commodityId": "3","commodityCount": 1,"isDelete": 0}]
}④ 批量增加两条，批量编辑两条
元数据：
{"id": 1,"name": "置办年货","isDelete": 0,"detailsList": [{"id": 1,"orderId": 1,"commodityName": "鞭炮","commodityId": "1","commodityCount": 1,"isDelete": 0},{"id": 2,"orderId": 1,"commodityName": "春联","commodityId": "2","commodityCount": 111,"isDelete": 0},{"id": 3,"orderId": 1,"commodityName": "牛","commodityId": "3","commodityCount": 1,"isDelete": 0},{"id": 14,"orderId": 1,"commodityName": "新增1","commodityId": "4","commodityCount": 1,"isDelete": 0},{"id": 15,"orderId": 1,"commodityName": "新增2","commodityId": "5","commodityCount": 1,"isDelete": 0}]
}入参：
{"id": 1,"name": "置办年货","isDelete": 0,"detailsList": [{"id": 1,"orderId": 1,"commodityName": "鞭炮(批量编辑)","commodityId": "1","commodityCount": 1,"isDelete": 0},{"id": 2,"orderId": 1,"commodityName": "春联(批量删除)","commodityId": "2","commodityCount": 111,"isDelete": 0},{"id": 3,"orderId": 1,"commodityName": "牛","commodityId": "3","commodityCount": 1,"isDelete": 0}]
}出参：
{"id": 1,"name": "置办年货","isDelete": 0,"detailsList": [{"id": 1,"orderId": 1,"commodityName": "鞭炮(批量编辑)","commodityId": "1","commodityCount": 1,"isDelete": 0},{"id": 2,"orderId": 1,"commodityName": "春联(批量删除)","commodityId": "2","commodityCount": 111,"isDelete": 0},{"id": 3,"orderId": 1,"commodityName": "牛","commodityId": "3","commodityCount": 1,"isDelete": 0}]
}⑤ 批量增加两条，批量删除两条
原数据：
{"id": 1,"name": "置办年货","isDelete": 0,"detailsList": [{"id": 1,"orderId": 1,"commodityName": "鞭炮","commodityId": "1","commodityCount": 1,"isDelete": 0},{"id": 2,"orderId": 1,"commodityName": "春联","commodityId": "2","commodityCount": 1,"isDelete": 0},{"id": 3,"orderId": 1,"commodityName": "牛","commodityId": "3","commodityCount": 1,"isDelete": 0}]
}入参：
{"id": 1,"name": "置办年货","isDelete": 0,"detailsList": [{"id": 1,"orderId": 1,"commodityName": "鞭炮","commodityId": "1","commodityCount": 1,"isDelete": 0},{"orderId": 1,"commodityName": "新增1","commodityId": "4","commodityCount": 1,"isDelete": 0},{"orderId": 1,"commodityName": "新增2","commodityId": "5","commodityCount": 1,"isDelete": 0}]
}出参：
{"id": 1,"name": "置办年货","isDelete": 0,"detailsList": [{"id": 1,"orderId": 1,"commodityName": "鞭炮","commodityId": "1","commodityCount": 1,"isDelete": 0},{"orderId": 1,"commodityName": "新增1","commodityId": "4","commodityCount": 1,"isDelete": 0},{"orderId": 1,"commodityName": "新增2","commodityId": "5","commodityCount": 1,"isDelete": 0}]
}⑥批量编辑两条，批量删除两条
元数据：
{"id": 1,"name": "置办年货","isDelete": 0,"detailsList": [{"id": 1,"orderId": 1,"commodityName": "鞭炮","commodityId": "1","commodityCount": 1,"isDelete": 0},{"id": 2,"orderId": 1,"commodityName": "春联","commodityId": "2","commodityCount": 1,"isDelete": 0},{"id": 3,"orderId": 1,"commodityName": "牛","commodityId": "3","commodityCount": 1,"isDelete": 0},{"id": 14,"orderId": 1,"commodityName": "删除1","commodityId": "4","commodityCount": 1,"isDelete": 0},{"id": 15,"orderId": 1,"commodityName": "删除2","commodityId": "5","commodityCount": 1,"isDelete": 0}]
}入参：
{"id": 1,"name": "置办年货","isDelete": 0,"detailsList": [{"id": 1,"orderId": 1,"commodityName": "鞭炮(edit)","commodityId": "1","commodityCount": 1,"isDelete": 0},{"id": 2,"orderId": 1,"commodityName": "春联(edit)","commodityId": "2","commodityCount": 1,"isDelete": 0},{"id": 3,"orderId": 1,"commodityName": "牛","commodityId": "3","commodityCount": 1,"isDelete": 0}]
}出参：
{"id": 1,"name": "置办年货","isDelete": 0,"detailsList": [{"id": 1,"orderId": 1,"commodityName": "鞭炮(edit)","commodityId": "1","commodityCount": 1,"isDelete": 0},{"id": 2,"orderId": 1,"commodityName": "春联(edit)","commodityId": "2","commodityCount": 1,"isDelete": 0},{"id": 3,"orderId": 1,"commodityName": "牛","commodityId": "3","commodityCount": 1,"isDelete": 0}]
}⑦ 批量新增两条，批量编辑两条，批量删除一条
元数据：
{"id": 1,"name": "置办年货","isDelete": 0,"detailsList": [{"id": 1,"orderId": 1,"commodityName": "鞭炮","commodityId": "1","commodityCount": 1,"isDelete": 0},{"id": 2,"orderId": 1,"commodityName": "春联","commodityId": "2","commodityCount": 1,"isDelete": 0},{"id": 3,"orderId": 1,"commodityName": "牛","commodityId": "3","commodityCount": 1,"isDelete": 0}]
}入参：
{"id": 1,"name": "置办年货","isDelete": 0,"detailsList": [{"id": 1,"orderId": 1,"commodityName": "鞭炮(edit)","commodityId": "1","commodityCount": 111111,"isDelete": 0},{"id": 2,"orderId": 1,"commodityName": "春联(edit)","commodityId": "2","commodityCount": 2222,"isDelete": 0},{"orderId": 1,"commodityName": "新增1","commodityId": "4","commodityCount": 4444,"isDelete": 0},{"orderId": 1,"commodityName": "新增2","commodityId": "5","commodityCount": 555,"isDelete": 0}]
}出参：
{"id": 1,"name": "置办年货","isDelete": 0,"detailsList": [{"id": 1,"orderId": 1,"commodityName": "鞭炮(edit)","commodityId": "1","commodityCount": 111111,"isDelete": 0},{"id": 2,"orderId": 1,"commodityName": "春联(edit)","commodityId": "2","commodityCount": 2222,"isDelete": 0},{"id": 20,"orderId": 1,"commodityName": "新增1","commodityId": "4","commodityCount": 4444,"isDelete": 0},{"id": 21,"orderId": 1,"commodityName": "新增2","commodityId": "5","commodityCount": 555,"isDelete": 0}]
}代码如下：
entity：
package com.example.demo.entity;import java.util.List;/*** @program: springboot_01* @description:* @author: guoyiguang* @create: 2021-01-16 12:37**/
public class CommodityOrder {private Integer id ;private String name ;private Integer isDelete;private List<CommodityOrderDetail> detailsList;public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}public Integer getIsDelete() {return isDelete;}public void setIsDelete(Integer isDelete) {this.isDelete = isDelete;}public List<CommodityOrderDetail> getDetailsList() {return detailsList;}public void setDetailsList(List<CommodityOrderDetail> detailsList) {this.detailsList = detailsList;}@Overridepublic String toString() {return "CommodityOrder{" +"id='" + id + '\'' +", name='" + name + '\'' +", isDelete=" + isDelete +", detailsList=" + detailsList +'}';}
}注意：重写equals和hashCode 只需要将id和orderId参与运算即可，因为其他字段值是可以变的，前段传的和后台查出来的不一样，但是他们是同一个对象
package com.example.demo.entity;import java.util.Objects;/*** @program: springboot_01* @description:* @author: guoyiguang* @create: 2021-01-16 12:39**/
public class CommodityOrderDetail {private Integer id ;private Integer orderId ;private String commodityName ;private String commodityId ;private Integer commodityCount ;private Integer isDelete;public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public Integer getOrderId() {return orderId;}public void setOrderId(Integer orderId) {this.orderId = orderId;}public String getCommodityName() {return commodityName;}public void setCommodityName(String commodityName) {this.commodityName = commodityName;}public String getCommodityId() {return commodityId;}public void setCommodityId(String commodityId) {this.commodityId = commodityId;}public Integer getCommodityCount() {return commodityCount;}public void setCommodityCount(Integer commodityCount) {this.commodityCount = commodityCount;}public Integer getIsDelete() {return isDelete;}public void setIsDelete(Integer isDelete) {this.isDelete = isDelete;}@Overridepublic String toString() {return "CommodityOrderDetail{" +"id='" + id + '\'' +", orderId='" + orderId + '\'' +", commodityName='" + commodityName + '\'' +", commodityId='" + commodityId + '\'' +", commodityCount=" + commodityCount +", isDelete=" + isDelete +'}';}@Overridepublic boolean equals(Object o) {if (this == o) return true;if (o == null || getClass() != o.getClass()) return false;CommodityOrderDetail that = (CommodityOrderDetail) o;return Objects.equals(id, that.id) &&Objects.equals(orderId, that.orderId);}@Overridepublic int hashCode() {return Objects.hash(id, orderId);}
}
package com.example.demo.entity.Vo;import com.example.demo.entity.CommodityOrderDetail;
import java.util.List;/*** @program: springboot_01* @description:* @author: guoyiguang* @create: 2021-01-16 12:37**/
public class CommodityOrderVo {private Integer id ;private String name ;private Integer isDelete;private List<CommodityOrderDetail> toEditDetailsList;public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}public Integer getIsDelete() {return isDelete;}public void setIsDelete(Integer isDelete) {this.isDelete = isDelete;}public List<CommodityOrderDetail> getDetailsList() {return toEditDetailsList;}public void setDetailsList(List<CommodityOrderDetail> detailsList) {this.toEditDetailsList = detailsList;}@Overridepublic String toString() {return "CommodityOrder{" +"id='" + id + '\'' +", name='" + name + '\'' +", isDelete=" + isDelete +", toEditDetailsList=" + toEditDetailsList +'}';}
}
Mapper ：
package com.example.demo.mapper;import com.example.demo.entity.CommodityOrder;
import com.example.demo.entity.Vo.CommodityOrderVo;
import org.apache.ibatis.annotations.Param;
import org.springframework.stereotype.Repository;@Repository
public interface CommodityOrderMapper {CommodityOrder getByOrderId(@Param("id") Integer id);int updateOrderAndDetails(CommodityOrderVo commodityOrderVo);
}
package com.example.demo.mapper;import com.example.demo.entity.CommodityOrder;
import com.example.demo.entity.CommodityOrderDetail;
import org.apache.ibatis.annotations.Param;
import org.springframework.stereotype.Repository;import java.util.List;@Repository
public interface CommodityOrderDetailMapper {int batchInsertDetails(List<CommodityOrderDetail> list);List<CommodityOrderDetail> selectListByOrderId(@Param("orderId") String orderId);}
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.example.demo.mapper.CommodityOrderMapper" ><resultMap id="BaseResultMap" type="com.example.demo.entity.CommodityOrder"><id column="id" property="id" jdbcType="INTEGER" /><result column="name" property="name" jdbcType="VARCHAR" /><result column="is_delete" property="isDelete" jdbcType="INTEGER" /><collection property="detailsList" javaType="java.util.ArrayList" ofType="com.example.demo.entity.CommodityOrderDetail"select="com.example.demo.mapper.CommodityOrderDetailMapper.selectListByOrderId" column="id" ><!--column="id" ： 将主表id 列上的值作为参数传进来 给collection了里 com.example.demo.mapper.CommodityOrderDetailMapper.selectList 作为实参先查出主表的结果, 然后主表记录数是几 就执行几次 collection 的select,javaType和ofType 写不写都行,select的值: 对应xml的namespace + 对应xml中的代码片段的id,column作为select语句的参数传入,如果只传一个参数id可以简写: column="id";传多个参数： column="{orderId=id,isDelete=is_delete}" ；orderId/isDelete 是定义的变量名, id/is_delete 是主表的字段id/isDelete,将字段值传给collection里的sql--><id column="id" property="id" jdbcType="INTEGER" /><result column="orderId" property="orderId" jdbcType="INTEGER" /><result column="commodity_name" property="commodityName" jdbcType="VARCHAR" /><result column="commodity_id" property="commodityId" jdbcType="VARCHAR" /><result column="commodity_count" property="commodityCount" jdbcType="INTEGER" /><result column="is_delete" property="isDelete" jdbcType="INTEGER" /></collection></resultMap><select id="getByOrderId" resultMap="BaseResultMap">select id, name, custom_id, is_delete from commodity_order where id = #{id} and is_delete = 0</select><!--修改订单主字段 同时批量修改订单明细子数据--><update id="updateOrderAndDetails" parameterType="com.example.demo.entity.Vo.CommodityOrderVo">update (<foreach collection="toEditDetailsList" item="item" open="(" separator=" union " close=")" index="index">select #{item.id} as detail_id, #{item.commodityName} as tmp_commodity_name, #{item.commodityCount} as tmp_commodity_count , #{item.isDelete} as isDelete</foreach> as tmpinner join commodity_order_detail d on d.id = tmp.detail_id and d.is_delete = 0inner join commodity_order o on o.id = d.order_id and o.is_delete = d.is_deleteand o.id = 1) set o.name = #{name},d.commodity_name = tmp.tmp_commodity_name,d.commodity_count = tmp.tmp_commodity_count,d.is_delete = tmp.isDeletewhere o.id = #{id}</update>
</mapper><?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.example.demo.mapper.CommodityOrderDetailMapper" ><resultMap id="BaseResultMap" type="com.example.demo.entity.CommodityOrderDetail"><id column="id" property="id" jdbcType="INTEGER" /><result column="order_id" property="orderId" jdbcType="INTEGER" /><result column="commodity_name" property="commodityName" jdbcType="VARCHAR" /><result column="commodity_id" property="commodityId" jdbcType="VARCHAR" /><result column="commodity_count" property="commodityCount" jdbcType="INTEGER" /><result column="is_delete" property="isDelete" jdbcType="INTEGER" /></resultMap><!-- 批量新增--><insert id="batchInsertDetails" parameterType="java.util.List">INSERT INTO commodity_order_detail(order_id,commodity_name ,commodity_id,commodity_count,is_delete)VALUES<foreach collection="list" item="item" separator=",">(#{item.orderId,jdbcType=VARCHAR},#{item.commodityName,jdbcType=VARCHAR},#{item.commodityId,jdbcType=VARCHAR},#{item.commodityCount,jdbcType=VARCHAR},0)</foreach></insert><!--根据主订单id获取对应子订单信息--><select id="selectListByOrderId" resultMap="BaseResultMap">select id, order_id, commodity_name, commodity_id, commodity_count, is_deletefrom commodity_order_detailwhere order_id = #{orderId}and is_delete = 0</select>
</mapper>service：
package com.example.demo.service;import com.example.demo.entity.CommodityOrder;
import com.example.demo.entity.Vo.CommodityOrderVo;public interface CommodityOrderService {CommodityOrder getByOrderId(Integer id);int updateOrderAndDetails(CommodityOrderVo commodityOrderVo);
}
package com.example.demo.service;import com.example.demo.entity.CommodityOrderDetail;import java.util.List;public interface CommodityOrderDetailService {int batchInsertDetails(List<CommodityOrderDetail> list);List<CommodityOrderDetail> selectListByOrderId(String orderId);
}
serviceImpl：
package com.example.demo.service.Impl;import com.example.demo.entity.CommodityOrder;
import com.example.demo.entity.CommodityOrderDetail;
import com.example.demo.entity.Vo.CommodityOrderVo;
import com.example.demo.mapper.CommodityOrderMapper;
import com.example.demo.service.CommodityOrderDetailService;
import com.example.demo.service.CommodityOrderService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.util.CollectionUtils;import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;/*** @program: springboot_01* @description:* @author: guoyiguang* @create: 2021-01-16 13:09**/
@Service
public class CommodityOrderServiceImpl implements CommodityOrderService {@AutowiredCommodityOrderMapper commodityOrderMapper;@AutowiredCommodityOrderDetailService commodityOrderDetailService;@Overridepublic CommodityOrder getByOrderId(Integer id){return commodityOrderMapper.getByOrderId(id);}@Overridepublic int updateOrderAndDetails(CommodityOrderVo commodityOrderVo) {// 新增数据的容器List<CommodityOrderDetail> addList = new ArrayList();// 获取表里数据CommodityOrder orderFromDb = commodityOrderMapper.getByOrderId(commodityOrderVo.getId());if (!CollectionUtils.isEmpty(orderFromDb.getDetailsList())) {List<CommodityOrderDetail> detailsFromDb = orderFromDb.getDetailsList();// 前段返回的订单明细 集合 中有数据if (!CollectionUtils.isEmpty(commodityOrderVo.getDetailsList())) {// 过滤出 detailsFromDb 没有的数据为新增 (也可以考虑 removeAll 不过原来的集合会改变)addList = commodityOrderVo.getDetailsList().stream()// contains 涉及到自定义对象的 是否一样，需要重写 equals 和 hasCode 方法；此处只需要 id，和orderId一样就认为是同一个对象// 如果把CommodityOrderDetail 里的所有属性 都参与 equals 和 hasCode，数据库里的一条数据 和前端 传过来根据id ，name 等其他字段判断的时候// 发现不一样，就认为这是两条不同的数据,所以重写 equals和hashCode 的时候只需要让id 和 orderId 参与运算即可.filter(detail -> !detailsFromDb.contains(detail)).collect(Collectors.toList());}}// 新增if (!CollectionUtils.isEmpty(addList)) {// 批量入库int count = commodityOrderDetailService.batchInsertDetails(addList);System.out.println("批量插入 明细表的 条数为--------------------------> "+ count);}// 修改（编辑 + 逻辑删除）// 修改 前端一般不传要删掉的订单明细id，只传要编辑的订单明细id和业务数据 commodityOrderVo.getEditList() 只包含了要编辑的业务数据// 获取要逻辑删除的数据 :（库里有,前端没有传的）List<CommodityOrderDetail> logicDeleteList = orderFromDb.getDetailsList().stream().filter(detail ->!commodityOrderVo.getDetailsList().contains(detail) ).map(de -> {// 设置成删除de.setIsDelete(1);return de;}).collect(Collectors.toList());if (!CollectionUtils.isEmpty(commodityOrderVo.getDetailsList()) &&!CollectionUtils.isEmpty(logicDeleteList) ) {// 要编辑的业务数据 + 要删除的业务数据commodityOrderVo.getDetailsList().addAll(logicDeleteList);}return commodityOrderMapper.updateOrderAndDetails(commodityOrderVo);}
}
package com.example.demo.service.Impl;import com.example.demo.entity.CommodityOrderDetail;
import com.example.demo.mapper.CommodityOrderDetailMapper;
import com.example.demo.service.CommodityOrderDetailService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;import java.util.List;/*** @program: springboot_01* @description:* @author: guoyiguang* @create: 2021-01-16 13:10**/
@Service
public class CommodityOrderDetailServiceImpl implements CommodityOrderDetailService {@AutowiredCommodityOrderDetailMapper commodityOrderDetailMapper;@Overridepublic int batchInsertDetails(List<CommodityOrderDetail> list) {return commodityOrderDetailMapper.batchInsertDetails(list);}@Overridepublic List<CommodityOrderDetail> selectListByOrderId(String orderId) {// 暂时不实现 ，因为目前是通过 主订单来操作 子表的return null;}
}
pom:
<?xml version="1.0"?><projectxsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><modelVersion>4.0.0</modelVersion><!-- 项目信息 begin --><groupId>com.microservice</groupId><artifactId>spring-web</artifactId><version>0.0.1-SNAPSHOT</version><name>spring-web</name><url>http://maven.apache.org</url><!-- 项目信息end --><!-- 属性配置 begin --><properties><project.build.sourceEncoding>UTF-8</project.build.sourceEncoding><project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding><java.version>1.8</java.version></properties><!-- 属性配置end --><!-- 父依赖 begin --><parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>1.4.1.RELEASE</version><relativePath /> <!-- lookup parent from repository --></parent><!-- 父依赖 end --><dependencies><!-- druid --><dependency><groupId>com.alibaba</groupId><artifactId>druid</artifactId><version>1.1.9</version></dependency><!-- 添加web包 begin --><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter</artifactId></dependency><!-- 该包中包含requestMapping restController 等注解 --><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency><!-- 添加web包 end --><!-- mybatis依赖 begin --><dependency><groupId>org.mybatis.spring.boot</groupId><artifactId>mybatis-spring-boot-starter</artifactId><version>1.1.1</version></dependency><!-- mybatis依赖 end --><!-- mysql数据库配置 begin --><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><version>8.0.22</version></dependency><!-- mysql数据库配置 end --><dependency><groupId>junit</groupId><artifactId>junit</artifactId><version>3.8.1</version><scope>test</scope></dependency><dependency><groupId>junit</groupId><artifactId>junit</artifactId><scope>test</scope></dependency></dependencies>
</project>配置文件：
server.port=8080
#redis
spring.redis.host=localhost
spring.redis.port=6379
#spring.redis.password=bigdata123
spring.redis.database=0
#spring.redis.timeout=0spring.redis.pool.maxTotal=8
spring.redis.pool.maxWaitMillis=1000
#spring.redis.pool.max-idle=8 # pool settings ...
#spring.redis.pool.min-idle=0
#spring.redis.pool.max-active=8
#spring.redis.pool.max-wait=-1
#spring.redis.sentinel.master= # name of Redis server
#spring.redis.sentinel.nodes= # comma-separated list of host:port pairs# 数据源配置
spring.datasource.url=jdbc:mysql://localhost:3306/sql_test?serverTimezone=UTC&characterEncoding=utf-8
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.username=root
spring.datasource.password=123456
#连接池配置
#spring.datasource.type=org.apache.commons.dbcp2.BasicDataSource#mybatis
#entity扫描的包名
mybatis.type-aliases-package=com.springboot.demo.model
#Mapper.xml所在的位置
mybatis.mapper-locations=classpath*:/mybatis/mapper/*Mapper.xml
# 下面这个配置报错： Invalid bound statement (not found): com.example.demo.mapper.RegionMapper.list
#mybatis.mapper-location=classpath*:/mybatis/mapper/*Mapper.xml
#开启MyBatis的二级缓存
mybatis.configuration.cache-enabled=true#pagehelper
pagehelper.helperDialect=mysql
pagehelper.reasonable=true
pagehelper.supportMethodsArguments=true
pagehelper.params=count=countSql#日志配置
logging.level.com.xiaolyuh=debug
logging.level.org.springframework.web=debug
logging.level.org.springframework.transaction=debug
logging.level.org.mybatis=debug# mybatis plus log
mybatis.configuration.log-impl =org.apache.ibatis.logging.stdout.StdOutImpl什么时候要写equals和hashCode？当两个对象比较是否相等，集合里是否含有这个自定义对象的时候？具体要哪些字段参与 hash计算根据业务来
对所有字段参与hash
package com.example.demo.entity;import java.util.Objects;/*** @program: springboot_01* @description:* @author: guoyiguang* @create: 2021-01-16 12:39**/
public class CommodityOrderDetail {private Integer id ;private Integer orderId ;private String commodityName ;private String commodityId ;private Integer commodityCount ;private Integer isDelete;public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public Integer getOrderId() {return orderId;}public void setOrderId(Integer orderId) {this.orderId = orderId;}public String getCommodityName() {return commodityName;}public void setCommodityName(String commodityName) {this.commodityName = commodityName;}public String getCommodityId() {return commodityId;}public void setCommodityId(String commodityId) {this.commodityId = commodityId;}public Integer getCommodityCount() {return commodityCount;}public void setCommodityCount(Integer commodityCount) {this.commodityCount = commodityCount;}public Integer getIsDelete() {return isDelete;}public void setIsDelete(Integer isDelete) {this.isDelete = isDelete;}@Overridepublic String toString() {return "CommodityOrderDetail{" +"id='" + id + '\'' +", orderId='" + orderId + '\'' +", commodityName='" + commodityName + '\'' +", commodityId='" + commodityId + '\'' +", commodityCount=" + commodityCount +", isDelete=" + isDelete +'}';}@Overridepublic boolean equals(Object o) {if (this == o) return true;if (o == null || getClass() != o.getClass()) return false;CommodityOrderDetail that = (CommodityOrderDetail) o;return Objects.equals(id, that.id) &&Objects.equals(orderId, that.orderId) &&Objects.equals(commodityName, that.commodityName) &&Objects.equals(commodityId, that.commodityId) &&Objects.equals(commodityCount, that.commodityCount) &&Objects.equals(isDelete, that.isDelete);}@Overridepublic int hashCode() {return Objects.hash(id, orderId, commodityName, commodityId, commodityCount, isDelete);}
}
测试代码：
CommodityOrderDetail cod1 = new CommodityOrderDetail();cod1.setId(1);cod1.setOrderId(1);cod1.setCommodityId("1");cod1.setCommodityName("苹果");cod1.setCommodityCount(1);cod1.setIsDelete(0);CommodityOrderDetail cod2 = new CommodityOrderDetail();cod2.setId(1);cod2.setOrderId(1);cod2.setCommodityId("1");cod2.setCommodityName("苹果");cod2.setCommodityCount(1);cod2.setIsDelete(0);CommodityOrderDetail cod3 = new CommodityOrderDetail();cod3.setId(1);cod3.setOrderId(1);cod3.setCommodityId("1");cod3.setCommodityName("苹果苹果");cod3.setCommodityCount(10000);cod3.setIsDelete(1);System.out.println("----------------------");// falseSystem.out.println(cod1 == cod2);// trueSystem.out.println(cod1.equals(cod2));System.out.println("----------------------");// falseSystem.out.println(cod1 == cod3);System.out.println("----------------------");// falseSystem.out.println(cod1.equals(cod3));
出现一个场景：
我认为只要 是 订单明细的id 和 orderId 值一样，我就认为这两个对象是一样的（等值的），即需要认为 cod1.equals(cod2) ;od2.equals(cod3) ;
cod1 , cod2 , cod3 是同一个对象
只需要hashCode和equals 的时候 对 id和orderId 参与运算即可，其他字段前端传过来和库里的可能不一样，就不参与 hash运算
package com.example.demo.entity;import java.util.Objects;/*** @program: springboot_01* @description:* @author: guoyiguang* @create: 2021-01-16 12:39**/
public class CommodityOrderDetail {private Integer id ;private Integer orderId ;private String commodityName ;private String commodityId ;private Integer commodityCount ;private Integer isDelete;public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public Integer getOrderId() {return orderId;}public void setOrderId(Integer orderId) {this.orderId = orderId;}public String getCommodityName() {return commodityName;}public void setCommodityName(String commodityName) {this.commodityName = commodityName;}public String getCommodityId() {return commodityId;}public void setCommodityId(String commodityId) {this.commodityId = commodityId;}public Integer getCommodityCount() {return commodityCount;}public void setCommodityCount(Integer commodityCount) {this.commodityCount = commodityCount;}public Integer getIsDelete() {return isDelete;}public void setIsDelete(Integer isDelete) {this.isDelete = isDelete;}@Overridepublic String toString() {return "CommodityOrderDetail{" +"id='" + id + '\'' +", orderId='" + orderId + '\'' +", commodityName='" + commodityName + '\'' +", commodityId='" + commodityId + '\'' +", commodityCount=" + commodityCount +", isDelete=" + isDelete +'}';}@Overridepublic boolean equals(Object o) {if (this == o) return true;if (o == null || getClass() != o.getClass()) return false;CommodityOrderDetail that = (CommodityOrderDetail) o;return Objects.equals(id, that.id) &&Objects.equals(orderId, that.orderId);}@Overridepublic int hashCode() {return Objects.hash(id, orderId);}
}
测试代码及结果：
CommodityOrderDetail cod1 = new CommodityOrderDetail();cod1.setId(1);cod1.setOrderId(1);cod1.setCommodityId("1");cod1.setCommodityName("苹果");cod1.setCommodityCount(1);cod1.setIsDelete(0);CommodityOrderDetail cod2 = new CommodityOrderDetail();cod2.setId(1);cod2.setOrderId(1);cod2.setCommodityId("1");cod2.setCommodityName("苹果");cod2.setCommodityCount(1);cod2.setIsDelete(0);CommodityOrderDetail cod3 = new CommodityOrderDetail();cod3.setId(1);cod3.setOrderId(1);cod3.setCommodityId("1");cod3.setCommodityName("苹果苹果");cod3.setCommodityCount(10000);cod3.setIsDelete(1);System.out.println("----------------------");// falseSystem.out.println(cod1 == cod2);// trueSystem.out.println(cod1.equals(cod2));System.out.println("----------------------");// falseSystem.out.println(cod1 == cod3);System.out.println("----------------------");// trueSystem.out.println(cod1.equals(cod3));
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