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 ...

SQL JOINs make it easy to find and fix missing data Your email has been sent Many people are confused by various JOIN operations supported by SQL. Learn to master the SQL command line with this crash ...

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 ...