SELECT TOP clause:

• TOP clause is used to fetch specific number of records from a table.
• This clause is very handy when we have huge table of thousands of record in it . And fetching data from these tables are quite time-consuming , in such situation TOP clause can be used to fetch limited number of records and saves processing time.
• In MySQL we use LIMIT and in Oracle we use ROWNUM clause in place of TOP clause.

Syntax for SQL Server:

SELECT TOP number|percent columnname(s)
FROM tablename;

Example:

SELECT TOP 5 * FROM Employee;

In the above query we are fetching top five employee records from Employee table.

Syntax for oracle:

SELECT columnname(s)
FROM tablename
WHERE ROWNUM <= number;

As we can see from the syntax ROWNUM is used in place of TOP clause for Oracle.

Example:

SELECT *
FROM Employee
WHERE ROWNUM <=3;

In the above example we are fetching top three employee records from Employee table.

Syntax for MySQL:

SELECT columnname(s)
FROM tablename
LIMIT number;

Example:

SELECT *
FROM Employee
WHERE LIMIT 5;

In the above query we are fetching top five employee records from Employee table.