FROM table1, table2 WHERE table1.keyfield=table2.keyfield When you execute a statement like this, SQL creates a new table—the results recordset—based on the contents of table1 and table2.

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 ...

The left join updates all rows in table A. Inner join only updates rows in table A where there is a matching ID in table B. You're working with different row sets. Now if you said something like: ...

SQL is the leading language for developing and querying databases, but it has a few quirks. In my last article, I shared 7 SQL mistakes to avoid. Now, let’s take a look at 9 best practices for ...

SQL Server 2016 lets you treat JSON objects like rows in a table, allowing you to use data from AJAX queries in joins, updates and any other SQL statement you can think of. SQL Server 2016 provides ...

Spark SQL: Apache’s Spark project is for real-time, in-memory, parallelized processing of Hadoop data. Spark SQL builds on top of it to allow SQL queries to be written against data.