SQL Less Than
What is the SQL Less Than Operator?
The SQL "Less Than" operator, denoted as "<", is used to compare values in a database table and retrieve rows where a specific column's value is less than a given criteria.
When you would use it
You would use the "Less Than" operator when you want to filter and retrieve data from a database table based on values that are less than a particular value or expression. This is particularly useful when you need to extract data that meets specific conditions related to lower values.
Syntax
The basic syntax for using the "Less Than" operator in an SQL query is as follows:
SELECT column1, column2
FROM table_name
WHERE column_name < value;
SELECT: Specifies the columns you want to retrieve.FROM: Specifies the table from which you want to retrieve data.WHERE: Specifies the condition for filtering rows.column_name: The name of the column you want to compare.value: The value or expression you want to compare the column with.
Parameter values
column_name: The name of the column you want to filter.value: The value or expression you want to compare against.
Example query
Assume we have a table named "products" with columns: "product_id," "product_name," and "price." Here's an example query using the "Less Than" operator:
SELECT product_name, price
FROM products
WHERE price < 25.00;
In this query, we're retrieving the product names and prices of products whose price is less than $25.00.
Example table response
Suppose the "products" table has the following data:
| product_id | product_name | price |
|---|---|---|
| 1 | Widget A | 19.99 |
| 2 | Widget B | 22.50 |
| 3 | Widget C | 25.00 |
| 4 | Widget D | 18.95 |
The query would return:
| product_name | price |
|---|---|
| Widget A | 19.99 |
| Widget B | 22.50 |
| Widget D | 18.95 |
Use cases
The "Less Than" operator is commonly used in various scenarios, including:
- Finding data that falls below specific numerical thresholds, such as searching for low-value products or transactions.
- Extracting data that is older than a given date or timestamp.
- Filtering records based on numeric comparisons in aggregate functions.
SQL languages this is available for
The "Less Than" operator is a standard feature supported by all major SQL database management systems (DBMS) and SQL-based languages, including but not limited to:
- MySQL
- PostgreSQL
- Oracle Database
- Microsoft SQL Server
- SQLite
- IBM Db2
In summary, the "Less Than" operator is a fundamental tool for filtering and retrieving data based on numerical comparisons in SQL databases. It is available in all major SQL database systems, allowing you to specify conditions for extracting rows with values less than your criteria.
