You can practice SQL queries for an interview by using online resources, such as:

1. SQLZoo: SQLZoo is an interactive website with a series of tutorials and examples of SQL queries. It allows you to practice your SQL skills with a variety of real-world scenarios and provides detailed explanations for each query.

2. W3Schools: W3Schools has an extensive SQL tutorial, providing an introduction to the SQL language as well as detailed examples of how to use it.

3. Code Academy: Code Academy has a range of interactive tutorials to help you learn SQL. It also provides practice quizzes and challenges to help you test your knowledge.

4. SQL Fiddle: SQL Fiddle is an online tool that allows you to write and test SQL queries in a virtual environment. It provides examples and tutorials to help you learn SQL quickly and effectively.

5. Stack Overflow: Stack Overflow is an online community where users can ask and answer questions related to programming and coding. It has a large number of questions related to SQL and other programming languages, which can be used to practice your query writing skills.