Technology Questions

Free command displays memory usage in linux.

sort() , rsort(), asort()
ksort()   , usort()
arsort()  , uksort()
natsort() , natcasesort()
array_multisort()

 -1 indicates the field is null

 0 indicates the field is not null

 -2 indicates the field is truncated

Exploratory testing: means testing an application without a test plan and test script. In exploring testing test explore the application on the basis on his knowledge. The tester has no knowledge about the application previously. He explores the application like an end user and try to use it. While using the application his main motive is to find the bugs which are in the application.

Specification-driven testing: means to test the functionality of software according to the user requirements. In this, tester inputs multiple data and monitors the outputs from, the test object. In this testing tester evaluate the showstopper bugs which break the major functionality of the application. This type of testing requires test plan and test.

 Test scenarios are derived from requirement documents. We follow each and every functionality (called business rules) mentioned in the requirement document. One functionality can have multiple business rules. For example, let us say in there is one requirement called “Login”. This “Login” may have various scenarios. For example, one scenario is, enter the right User ID and wrong password. The system should display an error message. Another scenario would be to enter wrong User ID and right Password. The system should display an error message. The third scenario could be to enter the right User Name and right Password. The system should allow the user to get into the system. This is how the test cases are derived from the requirement documents or from the Use Cases.

Java Collections Framework provides a well designed set of interfaces and classes that support operations on a collections of objects. The most basic interfaces that reside in the Java Collections Framework are:

Collection, which represents a group of objects known as its elements.

Set, which is a collection that cannot contain duplicate elements.

List, which is an ordered collection and can contain duplicate elements.

Map, which is an object that maps keys to values and cannot contain duplicate keys.

Business facts or measures and foreign keys are persisted in fact tables which are referred as candidate keys in dimension tables. Additive values are usually provided by the fact tables which acts as independent variables by which dimensional attributes are analyzed.

Attributes that are used to constrain and group data for performing data warehousing queries are persisted in the dimension tables.

Java uses primitive data types and hence is not a pure object oriented language.