Database Testing

What is Database Testing?
   
Database testing involves the tests to check the exact values which have been retrieved from the database by the web or desktop application. It basically includes the following:

• Data integrity testing
• Data validity testing
• Database performance related testing
• Testing of procedures, triggers, functions etc

Data should be matched correctly as per the records are stored in the database. Testers should check all the functionality which is happening on every action performed in the application. Actions can include deletion, addition or save options. Below is the discussed point that how to test database:

• First of all, tester should make sure that he understands all the application totally and which database is being used with the testing application.
• Figure out all the tables which exist for the application and try to write all the database queries for the tables to execute. This is the best process for the testers to perform the DB testing.

Database testing commands:

DDL

Data Definition Language (DDL) statements are used to define the database structure or schema and descriptions of how the data should reside in the database. It is used to create and modify the structure of database objects in database.

• CREATE - to create objects in the database
• ALTER - alters the structure of the database
• DROP - delete objects from the database
• TRUNCATE - remove all records from a table, including all spaces allocated for the records are removed
• COMMENT - add comments to the data dictionary
• RENAME - rename an object

DML

Data Manipulation Language (DML) statements are used for managing data. It mainly deals with data manipulation

• SELECT - retrieve data from the a database
• INSERT - insert data into a table
• UPDATE - updates existing data within a table
• DELETE - deletes all records from a table, the space for the records remain
• MERGE - UPSERT operation (insert or update)
• CALL - call a PL/SQL or Java subprogram
• EXPLAIN PLAN - explain access path to data
• LOCK TABLE - control concurrency

DCL

Data Control Language includes commands such as GRANT, and mostly concerns with rights, permissions and other controls of the database system. It is used to create rights, permissions, and referential integrity as well it is used to control access to database by securing it.

• GRANT - gives user's access privileges to database
• REVOKE - withdraw access privileges given with the GRANT command

TCL

Transaction Control (TCL) statements are used to manage the changes made by DML statements. It allows statements to be grouped together into logical transactions.

• COMMIT - save work done
• SAVEPOINT - identify a point in a transaction to which you can later roll back
• ROLLBACK - restore database to original since the last COMMIT
• SET TRANSACTION - Change transaction options like isolation level and what rollback segment to use