Limit Function in TERADATA

In Teradata, you can use the QUALIFY clause along with the ROW_NUMBER() function to achieve a similar effect as the LIMIT function in other database systems. 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 employee_id, first_name, last_name

FROM employees

QUALIFY ROW_NUMBER() OVER (ORDER BY employee_id) <= 5;

In this query:

- SELECT employee_id, first_name, last_name specifies the columns you want to retrieve.

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

- QUALIFY ROW_NUMBER() OVER (ORDER BY employee_id) <= 5 assigns a row number to each row based on the ordering by employee_id and then filters only those rows where the row number is less than or equal to 5.

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

If you also want to include additional columns, you can adjust the SELECT clause accordingly. Additionally, you can use the ORDER BY clause within the ROW_NUMBER() function to specify a different ordering if needed.