In SQL, the LAST_VALUE function allows us to access the last value in a set of rows according to a specified order. We can further filter the results using the HAVING clause, which is used to filter group rows created by the GROUP BY clause.

Syntax

The syntax for using LAST_VALUE with HAVING clause is as follows:

SELECT column1, ..., LAST_VALUE(column2) OVER (PARTITION BY column3 ORDER BY column4) AS last_value
FROM table_name
GROUP BY column1, ...
HAVING condition;

Example

Let’s say we have a table called “orders” with the following columns: “order_id”, “customer_id”, “product_name”, and “order_date”.

To find the last order date for each customer who has more than 3 orders, we can use the LAST_VALUE function with the HAVING clause. The SQL query would be as follows:

SELECT customer_id, 
       LAST_VALUE(order_date) OVER (PARTITION BY customer_id ORDER BY order_date) AS last_order_date
FROM orders
GROUP BY customer_id
HAVING COUNT(*) > 3;

In this example, we partition the result set by the “customer_id” column and order it by the “order_date”. We then use the LAST_VALUE function to retrieve the last order date for each customer. The HAVING clause filters the result set to only include customers who have more than 3 orders.

This query will give us a result set containing the “customer_id” and the corresponding “last_order_date” for all customers who have made more than 3 orders.

Conclusion

Using the LAST_VALUE function with the HAVING clause in SQL allows us to find the last value in a set of rows and further filter the results based on specific conditions. It is a powerful tool for analyzing data and extracting meaningful insights.

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