Make a separate row if a column contains comma-separated value

问题

Let's suppose we have a simple select query which return result like below

   FirstName          LastName                     PayScale
   -----------        ------------                ---------------
    Craig              L                             150000
    Alice,Lisa         simons                        100000

So if we have comma-separated first name, then I want result like this

   FirstName          LastName                     PayScale
   -----------        ------------                ---------------
    Craig              L                             150000
    Alice              simons                        100000
    Lisa               simons                        100000

回答1:

You can write a query as:

DECLARE @employee TABLE (FirstName  VARCHAR(100),
                         LastName   VARCHAR(100),
                         PayScale INT)

INSERT INTO @employee VALUES 
('Craig','L',150000) , 
('Alice,Lisa','simons',100000)



SELECT Split.a.value('.', 'VARCHAR(100)') AS FirstName  , LastName  ,PayScale
       FROM  (SELECT  CAST ('<M>' + REPLACE(FirstName, ',', '</M><M>') + '</M>' 
                             AS XML) AS FirstName ,  LastName    ,PayScale
               FROM  @employee) 
       AS A 
CROSS APPLY FirstName.nodes ('/M') AS Split(a)

来源：https://stackoverflow.com/questions/27498145/make-a-separate-row-if-a-column-contains-comma-separated-value