Multiple SELECT in INSERT INTO query

Question

I need a query that will sort data from Tab and put it into NewTab, which looks like this:

I'm using SQL Server 2008 R2 Express, and I've tried code:

INSERT INTO NewTab(Var1,Var2,Var3,DTime) VALUES (
    (SELECT Value FROM Tab WHERE VarName='Var1'),
    (SELECT Value FROM Tab WHERE VarName='Var2'),
    (SELECT Value FROM Tab WHERE VarName='Var3'),
    (SELECT DTime FROM Tab WHERE VarName='Var1')
    )

But server is returning and error:

Subquery returned more than 1 value. This is not permitted when the subquery follows =, !=, <, <= , >, >= or when the subquery is used as an expression.

I'm quite new to SQL and I'll be grateful if someone help me with that.

Answer 1

You seems to be trying to pivot the data. There are other ways to do it (i.e using PIVOT operator), but I guess that using old-school aggregate functions help us get a better idea of how data is processed:

SELECT DTime
, SUM(CASE WHEN varname = 'Var1' THEN value ELSE NULL END) AS [Var1]
, SUM(CASE WHEN varname = 'Var2' THEN value ELSE NULL END) AS [Var2]
, SUM(CASE WHEN varname = 'Var3' THEN value ELSE NULL END) AS [Var3]
FROM Tab
GROUP BY DTime