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 ...

Here's a look at different ways to query Hadoop via SQL, some of which are part of the latest edition of MapR's Hadoop distribution SQL: old and busted. Hadoop: new hotness. That’s the conventional ...