Sub queries are like queries with in the query. You can write subquery such that it will return single value or multiple values. Read more example and explanation.
Two kinds of Joins equi join and inner join mostly a confusion to all SQL developers. The given clear differences highly useful so that a basic learner can understand quickly.
SQL query is executed in two phases. The number one is Query processor and the other one is storage engine.
Three SQL rules to create a view. This is almost same in DB2, Oracle and Teradata. Also given ready made best example on how to create view and also to get data from view using SQL Query.
The quick 3 minute SQL quiz a really good tool to test your SQL knowledge. Start trying it today.
The popular ways to prevent deadlock in database while dealing with SQL queries written clearly such that even layman can understand quickly.