SQL 选择 2 列合二为一并组合它们
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Select 2 columns in one and combine them
提问by Gondim
Is it possible to select 2 columns in just one and combine them?
是否可以仅选择 2 列并将它们组合起来？
Example:
例子：
select something + somethingElse as onlyOneColumn from someTable
select something + somethingElse as onlyOneColumn from someTable
采纳答案by gjvdkamp
Yes, just like you did:
是的，就像你做的那样：
select something + somethingElse as onlyOneColumn from someTable
If you queried the database, you would have gotten the right answer.
如果你查询数据库，你会得到正确的答案。
What happens is you ask for an expression. A very simple expression is just a column name, a more complicated expression can have formulas etc in it.
发生的事情是你要求一个表达。一个非常简单的表达式只是一个列名，一个更复杂的表达式可以包含公式等。
回答by surya
(SELECT column1 as column FROM table )
UNION
(SELECT column2 as column FROM table )
回答by David Fox
Yes,
是的，
SELECT CONCAT(field1, field2) AS WHOLENAME FROM TABLE
WHERE ...
will result in data set like:
将导致数据集如下：
WHOLENAME
field1field2
回答by Brian
None of the other answers worked for me but this did:
其他答案都不适合我，但这确实适用：
SELECT CONCAT(Cust_First, ' ', Cust_Last) AS CustName FROM customer
回答by SupremeDud
Yes it's possible, as long as the datatypes are compatible. If they aren't, use a CONVERT() or CAST()
是的，只要数据类型兼容，就可以。如果不是，请使用 CONVERT() 或 CAST()
SELECT firstname + ' ' + lastname AS name FROM customers
回答by RubenM
The +operator should do the trick just fine. Keep something in mind though, if one of the columns is null or does not have any value, it will give you a NULLresult. Instead, combine +with the function COALESCEand you'll be set.
该+运营商应该做的伎俩就好了。但是请记住，如果其中一列为空或没有任何值，它会给您一个NULL结果。相反，结合+该功能COALESCE，您将被设置。
Here is an example:
下面是一个例子：
SELECT COALESCE(column1,'') + COALESCE(column2,'') FROM table1.
For this example, if column1is NULL, then the results of column2will show up, instead of a simple NULL.
对于此示例，如果column1是NULL，column2则将显示的结果，而不是简单的NULL。
Hope this helps!
希望这可以帮助！
回答by paxdiablo
Yes, you can combine columns easily enough such as concatenating character data:
是的，您可以很容易地组合列，例如连接字符数据：
select col1 | col 2 as bothcols from tbl ...
or adding (for example) numeric data:
或添加（例如）数字数据：
select col1 + col2 as bothcols from tbl ...
In both those cases, you end up with a single column bothcols, which contains the combined data. You may have to coerce the data type if the columns are not compatible.
在这两种情况下，您最终都会得到一个bothcols包含组合数据的列。如果列不兼容，您可能必须强制转换数据类型。
回答by user1313900
if one of the column is number i have experienced the oracle will think '+' as sum operator instead concatenation.
如果其中一列是我经历过的数字，则 oracle 会将“+”视为和运算符而不是串联。
eg:
例如：
select (id + name) as one from table 1; (id is numeric)
throws invalid number exception
抛出无效号码异常
in such case you can || operator which is concatenation.
在这种情况下，您可以 || 运算符是连接。
select (id || name) as one from table 1;
回答by Hisham Shaaban
I hope this answer helps:
我希望这个答案有帮助：
SELECT (CAST(id AS NVARCHAR)+','+name) AS COMBINED_COLUMN FROM TABLENAME;
回答by Arnoldiusss
Your syntax should work, maybe add a space between the colums like
您的语法应该有效，也许在列之间添加一个空格，例如
SELECT something + ' ' + somethingElse as onlyOneColumn FROM someTable
SELECT something + ' ' + somethingElse as onlyOneColumn FROM someTable
