Technology Questions

Free command displays memory usage in linux.

A PHP filter is used to validate and filter data coming from insecure sources.
To test, validate and filter user input or custom data is an important part of any web application.
The PHP filter extension is designed to make data filtering easier and quicker.

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 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.

 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.

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

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

HTML 5 does not use SGML or XHTML it’s completely a new thing so you do not need to refer DTD. For HTML 5 you just need to put the below doctype code which makes the browser identify that this is a HTML 5 document.