SQL Seeker

SQL Patterns

SQL Filtering Data

SQL Data Filtering Patterns

Data filtering with WHERE, LIKE, and IN supports dynamic query patterns.

Introduction to SQL Data Filtering

Filtering data is a crucial aspect of querying databases effectively. SQL provides various clauses like WHERE, LIKE, and IN to help you retrieve specific data that meets certain criteria. Understanding how to use these clauses can greatly enhance your ability to work with SQL databases.

Using the WHERE Clause

The WHERE clause is used to filter records that fulfill a specified condition. It is typically used in a SELECT statement but can also be employed with UPDATE and DELETE statements.

In this example, the query retrieves all records from the Employees table where the Department is 'Sales'.

Pattern Matching with LIKE

The LIKE operator is used to search for a specified pattern in a column. You can use the '%' wildcard to represent zero or more characters and the '_' wildcard for a single character.

This query selects all customers whose names start with the letter 'J'. The '%' wildcard allows for any subsequent characters.

Filtering with IN

The IN operator allows you to specify multiple values in a WHERE clause. It is a shorthand for multiple OR conditions.

Here, the query retrieves all products that are either in the 'Electronics' or 'Toys' category.

Combining Conditions for Advanced Filtering

SQL allows combining WHERE, LIKE, and IN with logical operators such as AND, OR, and NOT to create more complex queries.

This query selects orders that have been shipped and were ordered on or after January 1, 2023.

SQL Patterns

Next
Sorting Data