SQL 从子查询中选择 *
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Select * from subquery
提问by karel
I'd like to get sum of column1, sum of column2 and total sum. In Postgres I can do it this way: (notice the star)
我想得到 column1 的总和，column2 的总和和总和。在 Postgres 中，我可以这样做：（注意星号）
SELECT *, a+b AS total_sum FROM
(
SELECT SUM(column1) AS a, SUM(column2) AS b
FROM table
)
But in Oracle I get an syntax error and have to use this:
但是在 Oracle 中我得到一个语法错误并且必须使用这个：
SELECT a,b, a+b AS total_sum FROM
(
SELECT SUM(column1) AS a, SUM(column2) AS b
FROM table
)
I have really lot of columns to return so I do not want to write the column names again in the main query. Is there any easy solution?
我真的有很多列要返回，所以我不想在主查询中再次写入列名。有什么简单的解决办法吗？
I cannot use a+b in the inner query because there are not known at this place.
I do not want to use SELECT SELECT SUM(column1) AS a, SUM(column2) AS b, SUM(column1)+SUM(column2) AS total_sum.
我不能在内部查询中使用 a+b，因为在这个地方不知道。我不想使用SELECT SELECT SUM(column1) AS a, SUM(column2) AS b, SUM(column1)+SUM(column2) AS total_sum.
回答by Peter Lang
You can select every column from that sub-query by aliasing it and adding the alias before the *:
您可以通过为该子查询设置别名并在 之前添加别名来选择该子查询中的每一列*：
SELECT t.*, a+b AS total_sum
FROM
(
SELECT SUM(column1) AS a, SUM(column2) AS b
FROM table
) t
