Black-Box Testing Disadvantages

1.2.1 Black Box Testing in Database Testing
This type of testing does not require any knowledge of the internal working of the application for the tester as there is no need to access the source code of application and the tester is oblivious to the software architecture. Basically, while performing black-box testing, a tester will only interact with the user interface of the system by giving inputs and examining the corresponding outputs without any kind of knowledge about how and where these inputs are being worked on. Thus, Black-box testing includes testing of interfaces and integration with database, which involves:
• Verification of incoming data items
• Data mapping including meta data
• Verification of outgoing data items from query

• Execute module testing of database functions, views, SQL queries, triggers etc.
• Selects default values of table(s) in order to check consistency of database.
• Techniques such as condition coverage, cyclomatic complexity, statement coverage, decision coverage etc are used.
Various advantages and disadvantages of white box testing are following:
Table1.3 Advantages and Disadvantages of White-Box Testing
Advantages Disadvantages
• As the tester has knowledge of the source code, it becomes very easy to find out which type of data can help in testing the application effectively.
• It helps in optimizing the code.
• Extra lines of code can be removed which can bring in hidden defects.
• Due to the tester's knowledge about the code, maximum coverage is attained during test scenario writing. Due to the fact that a skilled tester is needed to perform white box testing, the costs are increased.
• Sometimes it is impossible to look into every nook and corner to find out hidden errors that may create problems as many paths will go untested.
• It is difficult to maintain white box testing as the use of specialized tools like code analyzers and debugging tools are

Black Box Testing Grey Box Testing White Box Testing
1 The Internal Workings of an application are not required to be known Somewhat knowledge of the internal workings are known Tester has full knowledge of the Internal workings of the application
2 Also known as closed box testing, data driven testing and functional testing Another term for grey box testing is translucent testing as the tester has limited knowledge of the insides of the application Also known as clear box testing, structural testing or code based testing
3 Performed by end users and also by testers and developers Performed by end users and also by testers and developers Normally done by testers and developers
4 Testing is based on external expectations - Internal behavior of the application is unknown Testing is done on the basis of high level database diagrams and data flow diagrams Internal workings are fully known and the tester can design test data accordingly
5 This is the least time consuming and exhaustive Partly time consuming and exhaustive The most exhaustive and time consuming type of testing
6 Not suited to algorithm testing Not suited to algorithm testing Suited for algorithm