Logical Operators
In this post , we will discuss about Logical Operators. AND Operator : AND Operator is used to filter the records based on two or more than two conditions. It is specified in the WHERE...
Author: Shikha Katariya
Deadlocks in SQL
For a transactional database , Deadlocks in SQL may be defined as a situation in which two or more oracle sessions are competing against the same data and waiting for each other to release...
Transaction Control Language (TCL Commands)
COMMIT : This command is used to save the users action until that particular point of time. Until and less commit is performed , the changes made by transaction are not made permanent. Syntax...
Data Manipulation Language ( DML Commands)
Data Manipulation Commands are used for managing the data within the database objects. These commands are not auto commit unlike DDL commands. Types of Data Manipulation Language ( DML Commands) : 1. SELECT...
Anonymous PL/SQL Block
Definition : The PL/SQL block that has no name is called Anonymous PL/SQL Block. Structure : Since the Anonymous Blocks have no names , therefore the header section is completely missing. They only consist...
Null Functions
Null Functions : Null Functions are used to handle Null values . Following different kinds of Null Functions are available in Oracle. 1. NVL Function : NVL stands for Null Value. This Function is...
ETL Testing Guide
Data Warehouse Concepts. Introduction – ETL Testing. ETL Development Life Cycle. ETL Testing Life Cycle. Test Strategies for ETL Testing.
Surrogate key In Data warehouse.
Defining Surrogate Key : Surrogate Key may be defined as a system generated key which is used to maintain unique records in the Data warehouse databases. Need for Surrogate key : We all know...
Slow Changing Dimensions in Informatica (SCD)
Defining Slow Changing Dimensions: Change in the city names for e.g. Madras to Chennai , Change in the price of the product , Changes in the residential location of the people , Changes in...
DUAL Table in Oracle
Defining Dual Table : DUAL is a Special table having one row and one column. The Datatype of the Column is Varchar2(1) , Column Name is ‘DUMMY’ and Value is ‘X’. It is created...