What are wildcards in SQL and how do I use them?

What are wildcards in SQL and how do I use them?

Wildcards in SQL are special characters that allow you to match patterns in your queries. The most common wildcards are '%' and ''. The '%' wildcard matches any sequence of characters, while the '' wildcard matches a single character.

Can you give me an example of using '%' in a SQL query?

Sure! If you want to find all customers whose names start with 'A', you can use the query: SELECT * FROM customers WHERE name LIKE 'A%'; This will return all names that begin with 'A'.

What about the '_' wildcard? How is it different?

The '_' wildcard is used to match a single character. For example, if you want to find all customers with a name that has 'a' as the second letter, you can use: SELECT * FROM customers WHERE name LIKE '_a%'; This will match names like 'Sam', 'Max', etc.

Are there any other wildcards I should know about?

In standard SQL, '%' and '_' are the primary wildcards. However, some databases may have additional features or functions for pattern matching, so it's good to check the documentation for your specific SQL database.