COALESCE is a very useful function, if you want to build a string of data from a field in a database table.

You can do the same with CURSOR and FETCH FROM, but COALESCE can do it way faster with less code.

Say, you have a table named Employee with following data under the field EmployeeName:
Bob
Joe
Sarah
Nicole

For some reason you want to have a variable that looks like this: Bob, Joe, Sarah, Nicole. With COALESCE you can do it very easy and fast:

DECLARE @EmpName varchar(100)
SELECT @EmpName = COALESCE(@EmpName + ', ', '') + CAST(EmployeeName AS varchar(100))
FROM Employee

If you do SELECT @EmpName you will get the result as mentioned above. Now, try to do that with CURSOR and FETCH FROM, you will be thankful that COALESCE is there.

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