Oracle: LIMIT Clause

By Atul Rai | Last Updated: August 15, 2023 Previous       Next

The LIMIT clause, also referred to as the “row limiting clause” is a SQL feature that enables you to restrict the number of rows returned by a query. This can be immensely beneficial when dealing with large datasets, as it helps improve query performance, reduces network traffic, and provides a more manageable result set for further analysis.

Syntax of the LIMIT Clause

The syntax of the LIMIT clause in Oracle is as follows:

SELECT column1, column2, ...
FROM table_name
WHERE condition
ORDER BY column_name
LIMIT row_count;

P.S. The LIMIT clause available from Oracle 12c Release 1 (12.1.0.2) version.

Limit the Dataset

Imagine you’re managing a online store with a vast product catalog. You want to retrieve a concise list of the top-selling products from the past month to analyze their performance. Here’s how you can achieve this using the Oracle LIMIT clause:

SELECT product_name, units_sold
FROM sales
WHERE sale_date >= SYSDATE - 30
ORDER BY units_sold DESC
LIMIT 10;

In this example, the query retrieves the names of the top 10 best-selling products within the last 30 days. The LIMIT clause ensures that only the specified number of rows (in this case, 10) are returned, giving you a focused dataset for analysis.

Similar Post: MySQL: LIMIT Clause

Version Availability

The LIMIT clause available for developers starting from Oracle 12c Release 1 (12.1.0.2), a similar functionality can be achieved using the FETCH FIRST clause with the OFFSET clause for more advanced control over result sets. The FETCH FIRST clause retrieves a specific number of rows from the beginning of the result set, while the OFFSET clause allows you to skip a specified number of rows before fetching the desired number of rows.

Here’s how the example query using FETCH FIRST and OFFSET would look:

SELECT product_name, units_sold
FROM sales
WHERE sale_date >= SYSDATE - 30
ORDER BY units_sold DESC
OFFSET 0 ROWS
FETCH FIRST 10 ROWS ONLY;

Summary

The Oracle LIMIT clause can streamline your queries, improve performance, and make data analysis more efficient than ever.

References

1. Limit Clause – OracleDoc
2. Oracle: TRUNC(number) Function
3. Oracle: RANK() Function