Limit Function in DB2

In IBM DB2, you can use the FETCH FIRST clause to limit the number of rows returned by a query. Here's how you can use it with an example:

Suppose you have a table called employees with columns employee_id, first_name, and last_name, and you want to retrieve the first 5 employees ordered by employee_id:

SELECT *

FROM employees

ORDER BY employee_id

FETCH FIRST 5 ROWS ONLY;

In this query:

- SELECT * selects all columns from the employees table.

- FROM employees specifies the table from which to retrieve the data.

- ORDER BY employee_id ensures that the results are sorted by the employee_id column.

- FETCH FIRST 5 ROWS ONLY restricts the result set to only include the first 5 rows.

This query will return the first 5 rows from the employees table, sorted by employee_id.

You can also use the OFFSET clause to skip a certain number of rows before retrieving the specified number of rows. For example, to skip the first 10 rows and retrieve the next 5:

SELECT *

FROM employees

ORDER BY employee_id

OFFSET 10 ROWS

FETCH FIRST 5 ROWS ONLY;

This query will skip the first 10 rows and return the next 5 rows from the employees table, sorted by employee_id.

Using FETCH FIRST with OFFSET allows you to paginate through large result sets efficiently.