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 ...

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 ...

I have a database table that acts as a log for a number of machines. Over the last few months, each time a machine's status has changed, I log a new entry ...

The Structured Query Language, used in the MySQL database, has great flexibility for selecting subsets of data from database tables. SQL's SELECT statement shows data from whole tables or any subset ...

Designing an appropriate set of indexes can be one of the more troubling aspects of developing efficient relational database applications. Perhaps, the most important thing you can do to assure ...

Now that you understand the basic structure of a SQL application, let's dissect the basis of information retrieval: the query. For many techies, especially those that focus on systems administration, ...

JSON has stolen some of XML's thunder with features such as human and machine readability, a lightweight, compact text structure and support for many software and hardware platforms. JSON (JavaScript ...