Technology Questions

- Sub Query also termed as Nested Query or Inner Query is used to get data from multiple tables.
- A sub query is added in the where clause of the main query.

There can be two types of subqueries:
a.) Correlated sub query :
- It can reference column in a table listed in the from list of the outer query but is not as independent as a query.
b.) Non-Correlated sub query :
- Results of this sub query are submitted to the main query or parent query.
- It is independent like a query

By using super call we can call super class constructors  from sub class constructors and we can initialize super class private data.

Dispatcher recieves the request from client and assigns the request to one of the work process.
Roll area: Each workprocess works in a particular memory that memory is known as Role Area, which consists of User context and session data.
ABAP- Processor :is an interpretor which can execute logic

- Yes, HTML 5 can get the location of a user with the use of Geolocation API.

- Use getCurrentPosition() method to get the user’s current position.

<?php
$tomorrow = mktime(0, 0, 0, date("m") , date("d")+1, date("Y"));
$lastmonth = mktime(0, 0, 0, date("m")-1, date("d"), date("Y"));
echo ($tomorrow-$lastmonth)/86400;
?>

In the mesh topology, each computer is connected to the other with a separate physical link in a network. It is most reliable topology as the network does not get down in case one of the nodes is failed.

The differences between HTML and HTML5 are:

- Document of HTML is very large as compare to the HTML5.

- Audio and Video tags are not present in HTML whereas HTML5 contains audio and video tags.

- Vector technology is not integral part of HTML whereas HTML5 Vector technology is the integral part of it.

- HTML supported by all old browsers whereas HTML5 is supported by new browser.

- In HTML web sockets are not available whereas in HTML5 Full duplex communication channel is present.

The header() function sends a raw HTTP header to a client. We can use header() function for redirection of pages. It is important to notice that  header()  must be called before any actual output is seen..