The PostgreSQL BETWEEN operator is a powerful and versatile tool used for filtering query results based on a specific range of values. This operator simplifies your SQL queries by allowing you to select rows that fall within a defined range, making it an essential component of effective database management.

Syntax of PostgreSQL BETWEEN Operator

The basic syntax for the PostgreSQL BETWEEN operator is as follows:

				
					column_name BETWEEN value1 AND value2;

				
			

Here, column_name represents the column you wish to filter, while value1 and value2 define the lower and upper bounds of the range, respectively. It’s crucial to note that the BETWEEN operator is inclusive, meaning both the lower and upper bounds are included in the range.

Using the PostgreSQL BETWEEN Operator with Dates and Timestamps

One of the most common use cases for the PostgreSQL BETWEEN operator is to filter rows based on date or timestamp ranges. To do this, you can simply use the operator with the appropriate date or timestamp column in your query.

Here’s an example:

				
					SELECT *
FROM orders
WHERE order_date BETWEEN '2022-01-01' AND '2022-12-31';

				
			

This query will return all rows from the orders table where the order_date falls within the specified range, inclusive of both the start and end dates.

Combining PostgreSQL BETWEEN Operator with Other Conditions

You can combine the BETWEEN operator with other SQL conditions using the AND or OR operators to create more complex filtering criteria.

Here’s an example:

				
					SELECT *
FROM employees
WHERE (salary BETWEEN 50000 AND 80000) AND (hire_date BETWEEN '2020-01-01' AND '2021-12-31');

				
			

This query will return all rows from the employees table where the salary is between 50,000 and 80,000 and the hire_date is between January 1, 2020, and December 31, 2021.

Using the PostgreSQL NOT BETWEEN Operator

The PostgreSQL NOT BETWEEN operator allows you to filter rows that do not fall within a specified range. The syntax is as follows:

				
					column_name NOT BETWEEN value1 AND value2;

				
			

Here’s an example:

				
					SELECT *
FROM products
WHERE price NOT BETWEEN 100 AND 500;

				
			

This query will return all rows from the products table where the price is not within the range of 100 and 500.

Working with NULL Values and the PostgreSQL BETWEEN Operator

When using the PostgreSQL BETWEEN operator, it’s essential to understand how NULL values are handled. Any row with a NULL value in the specified column will not be included in the result set, regardless of the range specified in the query.

To include rows with NULL values in the result set, you can use the IS NULL condition in combination with the BETWEEN operator.

Here’s an example:

				
					SELECT *
FROM products
WHERE (price BETWEEN 100 AND 500) OR (price IS NULL);

				
			

This query will return all rows from the products table where the price is within the range of 100 and 500 or where the price is NULL.

Optimizing Performance with the PostgreSQL BETWEEN Operator

To ensure optimal performance when using the PostgreSQL BETWEEN operator, it’s crucial to index the columns used in the query. This can significantly improve query execution time, especially in large databases.

To create an index on a specific column, you can use the following syntax:

				
					CREATE INDEX index_name ON table_name(column_name);

				
			

By following these best practices and utilizing the PostgreSQL BETWEEN operator effectively, you can create efficient and streamlined SQL queries to extract the precise data you need from your database.

Using the PostgreSQL BETWEEN Operator with Text Values

The PostgreSQL BETWEEN operator can also be used with text values for filtering based on lexicographic order. This enables you to retrieve rows with text values that fall within a specified range.

Here’s an example:

				
					SELECT *
FROM customers
WHERE last_name BETWEEN 'A' AND 'M';

				
			

This query will return all rows from the customers table where the last_name starts with a letter between A and M, inclusive.

Utilizing BETWEEN with Numerical Data Types

The BETWEEN operator is also suitable for use with various numerical data types, such as integers, floats, and decimals. This versatility makes it a valuable tool for working with a wide range of data in PostgreSQL.

Here’s an example:

				
					SELECT *
FROM inventory
WHERE quantity BETWEEN 10 AND 100;

				
			

This query will return all rows from the inventory table where the quantity is between 10 and 100, inclusive.

PostgreSQL BETWEEN Operator and Aggregate Functions

You can use the PostgreSQL BETWEEN operator in conjunction with aggregate functions like COUNT, SUM, or AVG to perform calculations on specific data ranges.

Here’s an example:

				
					SELECT COUNT(*)
FROM sales
WHERE revenue BETWEEN 1000 AND 10000;

				
			

This query will return the number of rows from the sales table where the revenue is between 1,000 and 10,000.

Wrap up

The PostgreSQL BETWEEN operator is a versatile and powerful tool that simplifies the process of filtering query results based on specific value ranges. By understanding its syntax and use cases, you can create more efficient and precise SQL queries that extract the exact data you need from your PostgreSQL database.

Whether you’re working with dates, text, or numerical values, the PostgreSQL BETWEEN operator provides an effective and streamlined solution for defining and filtering ranges in your queries.

Check how to install PostgreSQL: https://softwareto.tech/how-install-postgresql-on-windows/


Thanks for reading. Happy coding!