Data Types
What is a Data Type?? A data type is something that assigns some predefined characteristics to the values and tells the SQL engine , what type of value it is and helps to differentiate...
Category: ETL Testing
Data Dictionary
What is Data dictionary ? Data Dictionary is basically a repository which contains data about the database such as information about tables , column names,their length , datatypes, attributes and other database structures etc....
Internal Working of Query Execution
When we execute an SQL statement e.g. SELECT * FROM EMP , Lets see what happens behind the scene i.e Internal working of query execution.In other words , Life cycle of an SQL statement...
Most Important …Live Project Scenarios
As we have understanding of all the modules required for ETL testing i.e. Data Warehouse , UNIX , SQL , ETL Concepts , Now its time to integrate the knowledge gained so far and...
ETL Testing Life Cycle
Like any other testing process , ETL Testing also goes through various phases called ETL Testing Life Cycle 1. Business and Requirement Analysis : This step involves reviewing and analyzing – Business Requirement Document...
Data Marts
What is a Data Mart ?? A Data Mart is a subset or form of Data Warehouse only but its scope is limited to a particular subject.In other words, It is a specific repository...
Metadata And Data Warehousing
1. Metadata What is Metadata??? Metadata may be defined as’ Data about data’ or ‘Data ( mostly definitions) about the structures containing other data’ . for e.g. a table has four columns , two...
Data warehouse Architecture and Process Flow.
Depending upon the business requirements and the budget , different data Warehouse may have different architectures Types Data Warehouse Architecture – Type 1 : Source (OLTP) —–> Staging Area ——> Data Warehouse ——> Reporting...
Types of Constraints
In the Previous post we studied about ‘ What are Constraints ? ‘. Now we will read about different Types of Constraints. What are the Different Types of Constraints : 1. NOT NULL Constraint...
Constraints in SQL
What are Constraints ?? Constraints may be defined as rules or conditions applied on the data columns of the table, that restrict the type of data entering into the table.They act as filter between...