Concat two column in a select statement sql server 2005

问题

How to Concat two column in a select statement sql server 2005?

Here is my statement Select FirstName,secondName from Table...

Now i did try concating secondName with FirstName by using

Select FirstName + ' ' + secondName from Table

But some values are NULL in secondName column for some records.. My select statement returns NULL instead of FirstName.. I want to have FirstName if secondName is NULL ..

回答1:

SELECT FirstName + ISNULL(' ' + SecondName, '') from Table

回答2:

If one of your fields is numeric then you can cast it to a string as follows:

SELECT FirstName + ISNULL(' ' + SecondName, '') + ' age(' + CONVERT(nvarchar,age) + ')' from Table

回答3:

do like this :

 select cast( FirstName as varchar)+' '+cast( secondName as varchar) from table

来源：https://stackoverflow.com/questions/2137835/concat-two-column-in-a-select-statement-sql-server-2005