Assume we have a table Emp (EmpName VARCHAR(50), Age INT)
Query 1:
INSERT INTO Emp(EmpName, Age)
SELECT 'Ravi Kiran', 36
Query 2:
INSERT INTO Emp(EmpName, Age)
VALUES ('Ravi Kiran', 36)
Both the queries will achieve the same result. But which one is better? Run the below code:
SET NOCOUNT ON
PRINT CONVERT(VARCHAR, GETDATE(), 121)
INSERT INTO Emp(EmpName, Age)
SELECT 'Ravi Kiran', 36
PRINT CONVERT(VARCHAR, GETDATE(), 121)
INSERT INTO Emp(EmpName, Age)
VALUES ('Ravi Kiran', 36)
PRINT CONVERT(VARCHAR, GETDATE(), 121)
The result is:
2010-11-23 23:04:08.617
2010-11-23 23:04:08.640
2010-11-23 23:04:08.640
The INSERT...SELECT took 23 milliseconds where as INSERT...VALUES took 0 milliseconds. Now you know!
So, if you want to insert a single record in a table, use INSERT...VALUES instead of INSERT...SELECT.
