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SQL TOP, LIMIT or ROWNUM Clause

The SQL SELECT TOP Clause

The SELECT TOP clause is used to specify the number of records to return.
The SELECT TOP clause is useful on large tables with thousands of records. Returning a large number of records can impact on performance.
Note: Not all database systems support the SELECT TOP clause. MySQL supports the LIMIT clause to select a limited number of records, while Oracle uses ROWNUM.
SQL Server / MS Access Syntax:
SELECT TOP number|percent column_name(s)
FROM table_nameWHERE condition;
MySQL Syntax:
SELECT column_name(s)
FROM table_nameWHERE condition
LIMIT number;
Oracle Syntax:
SELECT column_name(s)
FROM table_name
WHERE ROWNUM <= number;

Demo Database

Below is a selection from the "Customers" table in the Northwind sample database:
CustomerIDCustomerNameContactNameAddressCityPostalCodeCountry
1
Alfreds FutterkisteMaria AndersObere Str. 57Berlin12209Germany
2Ana Trujillo Emparedados y heladosAna TrujilloAvda. de la Constitución 2222México D.F.05021Mexico
3Antonio Moreno TaqueríaAntonio MorenoMataderos 2312México D.F.05023Mexico
4
Around the HornThomas Hardy120 Hanover Sq.LondonWA1 1DPUK
5Berglunds snabbköpChristina BerglundBerguvsvägen 8LuleåS-958 22Sweden


SQL TOP, LIMIT and ROWNUM Examples

The following SQL statement selects the first three records from the "Customers" table:

Example

SELECT TOP 3 * FROM Customers;
Try it Yourself »
The following SQL statement shows the equivalent example using the LIMIT clause:

Example

SELECT * FROM Customers
LIMIT 3;
Try it Yourself »
The following SQL statement shows the equivalent example using ROWNUM:

Example

SELECT * FROM Customers
WHERE ROWNUM <= 3;

SQL TOP PERCENT Example

The following SQL statement selects the first 50% of the records from the "Customers" table:

Example

SELECT TOP 50 PERCENT * FROM Customers;
Try it Yourself »

ADD a WHERE CLAUSE

The following SQL statement selects the first three records from the "Customers" table, where the country is "Germany":

Example

SELECT TOP 3 * FROM Customers
WHERE Country='Germany';
Try it Yourself »
The following SQL statement shows the equivalent example using the LIMIT clause:

Example

SELECT * FROM Customers
WHERE Country='Germany'
LIMIT 3;
Try it Yourself »
The following SQL statement shows the equivalent example using ROWNUM:

Example

SELECT * FROM Customers
WHERE Country='Germany' AND ROWNUM <= 3;



                                                                         






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