Question

所以我有一个sql表，它将保存一个像这样的ID

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| RecordID | Date | Price
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| 1 | 8/31/2016 | 49
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| 2 | 8/31/2016 | 101
--------------------------------------------------

我还有3个其他表可以保存有关此ID的信息，并且可以包含不同数量的列

Table 1
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| RecordID | Date | Price | Name
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| 1 | 8/31/2016 | 50 | System
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Table 2
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| RecordID | Date | Price | Coupon
--------------------------------------------------
| 2 | 8/31/2016 | 100 | 7
--------------------------------------------------

但ID在它们之间分开。含义表1可以具有ID 1，然后表2可以具有ID 2，依此类推。 ID只能存在于三个表中的一个中。

所以我的愿望是创建一个视图，我可以从原始表中获取ID和价格，并找到此ID存在于哪个表中并将它们放在一起，就像这样

---------------------------------------------------
| RecordID | Date | Price1 | Price2
--------------------------------------------------
| 1 | 8/31/2016 | 49 | 50
--------------------------------------------------
| 2 | 8/31/2016 | 101 | 100
--------------------------------------------------

Answer 1

您可以使用[{ "id": 0, "value": "Lorem test Ipsuver since the 1500s,but also the leap into electronic typesetting, remaining essentially unchanged." }, { "id": 1, "value": "-19170aee171f a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged." }, { "id": 2, "value": "19-9de6-19170aee171f a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged." }, { "id": 3, "value": "ee171f a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged." }]和LEFT OUTER JOINS。

来执行此操作

假设您有一个名为coalesce的主表和另外3个名为tRecords，tInfo1和tInfo2的表，所有这些表都有tInfo3和{ {1}}列：

RecordID

Answer 2

根据您在表格中的数据类型，考虑创建一个视图以合并其他3个表格的结果，以制作虚拟组合表：

create view vRecordCombo
select RecordId, Date, Price, Name as 'InfoString', NULL as 'InfoValue'
from table1
UNION ALL
select RecordId, Date, Price, NULL as 'InfoString', Coupon as 'InfoValue'
from table2

然后你可以对组合进行连接，好像它是包含所有记录的单个表。

创建用于检查多个表中的数据的SQL视图

2 个答案: