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1/03/2018

SQL Index Index in sql is created on existing tables to retrieve the rows quickly. When there are thousands of records in a table, retr...
SQL Subquery Subquery  or  Inner query  or  Nested query  is a query in a query. SQL subquery is usually added in the WHERE Clause of the...
SQL Views A VIEW is a virtual table, through which a selective portion of the data from one or more tables can be seen. Views do not cont...
SQL Joins SQL Joins are used to relate information in different tables. A Join condition is a part of the sql query that retrieves rows f...
SQL Constraints Integrity Constraints are used to apply business rules for the database tables. The constraints available in SQL are  F...