Enhancing your proficiency with SQL's LIKE operator is essential for effective pattern matching in database queries. This guide provides practical exercises and real-world examples to help you master LIKE queries and advance your SQL programming skills.

Understanding the SQL LIKE Operator

The LIKE operator is used in a WHERE clause to search for a specified pattern in a column. It supports two main wildcard characters:

• Percent sign %: Represents zero, one, or multiple characters.

• Underscore _: Represents a single character.

For a comprehensive overview, refer to AI2sql's Comprehensive List of SQL Commands.

Practical Examples of LIKE Queries

1. Finding Names Starting with a Specific Letter

   To retrieve customers whose names start with 'A':

   
   

2. Locating Products Containing a Specific Word

   To find products with 'phone' in their names:

   
   

3. Identifying Emails from a Specific Domain

   To select all Gmail users:

For more detailed tutorials, consider AI2sql's Guide to the Not Equal Operator.

Advanced LIKE Query Techniques

1. Case-Insensitive Searches

   To perform a case-insensitive search (behavior may vary by database system):

   
   

2. Combining Multiple Patterns

   To match multiple patterns:

For an in-depth exploration, visit AI2sql's Mastering Dates in SQL: Queries, Formats, and Functions Explained.

Best Practices for Using LIKE in SQL

• Optimize Performance: Avoid leading wildcards (e.g., '%pattern') as they can hinder index usage and slow down queries.

• Use Precise Patterns: Define clear patterns to minimize unintended matches.

• Consider Case Sensitivity: Be aware of how your database handles case sensitivity in pattern matching.

For additional insights, refer to AI2sql's How to Practice SQL in a Playful Way.

Practice Exercises

1. Retrieve Cities Starting with 'New'

   
   

2. Find Products with Specific Codes

   
   

3. Select Contacts with '.org' Emails

Regular practice with these exercises will enhance your proficiency in using the LIKE operator for effective pattern matching in SQL.

For more practice exercises and tutorials, explore AI2sql's SQL AI Formatter, Validator & Beautifier.