Suppose we have a simple query like this:
SELECT x
FROM t
WHERE t.y = z
If we have one record in the result set, I want to set variable @v
to that one value. If we have two or more records, I'd like the results to be separated by a comma and a space. What is the best way to write this T-SQL code?
Example:
result set of 1 record:
Value1
result set of 2 records:
Value1, Value2
result set of 3 records:
Value1, Value2, Value3
this will give you the list of values in a comma separated list
create table #temp
(
y int,
x varchar(10)
)
insert into #temp values (1, 'value 1')
insert into #temp values (1, 'value 2')
insert into #temp values (1, 'value 3')
insert into #temp values (1, 'value 4')
DECLARE @listStr varchar(255)
SELECT @listStr = COALESCE(@listStr+', ', '') + x
FROM #temp
WHERE #temp.y = 1
SELECT @listStr as List
drop table #temp