A common SQL habit is to use SELECT * on a query, because it’s tedious to list all the columns you need. Plus, sometimes those columns may change over time, so why not just do things the easy way? But ...

Read this SQL tutorial to learn when to use SELECT, JOIN, subselects and UNION to access multiple tables with a single statement. It’s sometimes difficult to know which SQL syntax to use when ...

Unlock the full InfoQ experience by logging in! Stay updated with your favorite authors and topics, engage with content, and download exclusive resources. Ramya Krishnamoorthy shares a detailed case ...

The latest problem New York City restaurants are facing: Restaurants in the city can open at 50 percent capacity, and some customers don’t want to leave as reunion dinners and drinks drag on. Now, ...

Constraints in SQL are used to define rules for the table and columns in a database and also make sure that data are accurate and trusted in the database. Constraints are responsible for the ...

The indexes on a the tables of a large database make a huge difference in its performance and utility. Without an index, locating a single record in a large table can take several seconds; with the ...