supriyak Archive
Do you remember signing your class attendance sheet on behalf of your friend (well of course your teacher doesn’t have to know :)). That is called Proxy. It means “in place of” or “on behalf”. The Proxy Pattern comes
Singleton Pattern is one of the Creational design pattern. The singleton pattern puts restriction on object creation process; it restricts the instantiation of a class to one object. If we are using Singleton pattern, no need to
JOIN clause is used to combine data from two or more tables, after joining it comes as a single set of data and we can call it Result set. Tables are combined using JOIN clause by using
QAs also use UNION clause frequently if need to do through testing of application functionalities with data. By using the UNION operator, we can combine the results of 2 or more SELECT statements and at the same
The GROUP BY clause is used to organize identical data into groups often with the help of 5 Aggregate functions ie. COUNT, MIN, MAX, AVG, SUM. GROUP BY clause is used with SELECT statement and it group
In SQL, ORDER BY clause is used to sort the records of the table. It is used with SELECT statement. Using this clause, we can sort the data by Ascending or Descending order. By default, ORDER BY
DELETE Statement is used to permanently removes existing records from a given table. Most of the time QAs won’t have permission to perform this command on Development or Production environment. But they can do it on their
UPDATE Statement is also frequently used by Testers and QAs. UPDATE is used to modify already existing records from the database table. In this article we will see how we can modify single as well as multiple
Many times, QAs don’t find sufficient data in QA environment for testing. So they need to create some dummy data specific to their test cases. They also need to add some negative data to verify negative conditions.
I believe WHERE clause is the most frequently used clause with SELECT statement by QAs. WHERE clause is not a compulsory clause in a SQL query, but a optional one to apply filter on the given table.
The use of SQL is not limited to developers only. If you are a Tester or QA professional, you also need to run some tests against databases, verify data using some tool. In short, database testing is
The Abstract Factory Pattern is one of the creational design patterns. We can say Abstract Factory patterns acts as a super-factory which produces other factories. The role of the Abstract Factory is to provide an interface for creating families
