如何在Oracle中从具有相同列名的两个表中检索数据

Question

我有两个表，一个工作表，另一个是备份表。 两个表都有相同的列。 现在，我希望在单个查询中来自两个表的几列数据。

有可能在单个查询吗？

表名： transationdetails workingtable transationdetails_backup是备份表

例如，我在这里编写单个查询：

select txnid as txnid
     , date as transactiondate
     , amount as amount 
  from transationdetails;

select txnid as txnid
     , date as transactiondate
     , amount as amount 
  from transationdetails_backup;

预期结果：

select txnid as txnid
     , date as transactiondate
     , amount as amount 
  from transationdetails and transationdetails_backup;

Answer 1

试试这个代码：

SELECT * FROM transationdetails 
UNION ALL
SELECT * FROM transationdetails_backup;

我相信简单的UNION ALL可以满足您的需求。

Answer 2

您可以像在MySQL中一样使用Concat函数，最简单的方法就是

|| （双管道，要连接的列之间）

EX :
select a.id , (a.id||a.name||b.job||a.stats) as backupDetail 
from "FirstTable" as a
inner join "SecondTable" as b on b.id = a.id 
Where a.id="YourParameter";

Answer 3

这将工作：

select txnid as txnid, date as transactiondate, amount as amount from transationdetails union all select txnid as txnid, date as transactiondate, amount as amount from transationdetails_backup;