SQL Server: Query fast, but slow from procedure

 I had the same problem as the original poster but the quoted answer did not solve the problem for me. The query still ran really slow from a stored procedure.

I found another answer here "Parameter Sniffing", Thanks Omnibuzz. Boils down to using "local Variables" in your stored procedure queries, but read the original for more understanding, it's a great write up. e.g.

Slow way:

CREATE PROCEDURE GetOrderForCustomers(@CustID varchar(20))
AS
BEGIN
    SELECT * 
    FROM orders
    WHERE customerid = @CustID
END

Fast way:

CREATE PROCEDURE GetOrderForCustomersWithoutPS(@CustID varchar(20))
AS
BEGIN
    DECLARE @LocCustID varchar(20)
    SET @LocCustID = @CustID

    SELECT * 
    FROM orders
    WHERE customerid = @LocCustID
END

Hope this helps somebody else, doing this reduced my execution time from 5+ minutes to about 6-7 seconds.