Question

我缺乏SQL经验，需要将多层过滤器应用于多个表以进行比较。

表1：

Order_Number Step_Name数据Parameter_Name
12 step4 const1 P1
12 step4 const2 P2
12 step4 value1 P3
30 step6 const3 P1
30 step6 const4 P2
30 step6 value2 P3

所有表格格式相同，数据值不同。订单号可能因表而异。

我想这样做：

仅在Step_Name = step1和step8之间搜索行
查找Order_Number匹配（P1 = const1和P2 = const2）
在相同的订单号组中保存P3行。
显示所有行（每个表中一行）：

Order_Number表数据Parameter_Name
12 table1 value1 P3
12 table2 value2 P3
14 table3 value3 P3

非常感谢您的帮助！

Answer 1

您需要根据需要添加尽可能多的union all...select部分：

select
    order_number,
    'table1' as `table`,
    data,
    prameter_name
from
    table1 t1p3
where
    step_name in ('step1', 'step2', 'step3', 'step4', 'step5', 'step6', 'step7', 'step8') and
    parameter = 'p3' and
    exists (
        select
            'x'
        from
            table1 t1p1
        where
            t1p1.order_number = t1p3.order_number and
            t1p1.step_name = t1p3.step_name and
            t1p1.parameter = 'p1' and
            t1p1.data = 'const1'
    ) and exists (
        select
            'x'
        from
            table1 t1p2
        where
            t1p2.order_number = t1p3.order_number and
            t1p2.step_name = t1p3.step_name and
            t1p2.parameter = 'p2' and
            t1p2.data = 'const2'
    ) 
union all
select
    order_number,
    'table2',
    data,
    prameter_name
from
    table2 t2p3
where
    step_name in ('step1', 'step2', 'step3', 'step4', 'step5', 'step6', 'step7', 'step8') and
    parameter = 'p3' and
    exists (
        select
              'x'
        from
            table2 t2p1
        where
            t2p1.order_number = t2p3.order_number and
            t2p1.step_name = t2p3.step_name and
            t2p1.parameter = 'p1' and
            t2p1.data = 'const1'
    ) and exists (
        select
            'x'
        from
            table2 t2p2
        where
            t2p2.order_number = t2p3.order_number and
            t2p2.step_name = t2p3.step_name and
            t2p2.parameter = 'p2' and
            t2p2.data = 'const2'
    )

sql查询将多个过滤器应用于多个表

1 个答案: