How to select first ‘n’ records from a table?

The SELECT TOP clause is used to specify the number of records to return. The SELECT TOP clause can be very useful on large tables with thousands of records. Returning a large number of records can impact on performance.

Example

CREATE TABLE [dbo].[Emp]

(

[EmpID] [int] IDENTITY(1,1) NOT NULL,

[EmpName] [varchar](50) NULL,

)

INSERT INTO EMP(EmpName)VALUES('ABC')

INSERT INTO EMP(EmpName)VALUES('CDE')

INSERT INTO EMP(EmpName)VALUES('PQR')

INSERT INTO EMP(EmpName)VALUES('XYZ')

INSERT INTO EMP(EmpName)VALUES('NML')

With Top Clause SELECT Top 3 Records

SELECT Top 3 * FROM Emp

Without TOP Clause

SELECT * FROM Emp e1

WHERE (SELECT COUNT(*) FROM Emp e2 WHERE e2.EmpID<e1.EmpID)<3

Output

Emp_ID	Emp_Name
1	ABC
2	CDE
3	PQR

Comments

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