Interview Questions for Fresher Set-4

 31) What does the unset() function mean?

The unset() function is dedicated for variable management. It will make a variable undefined.

32) What does the unlink() function mean?

The unlink() function is dedicated for file system handling. It simply deletes the file given as entry.

33) How do I check if a given variable is empty?

If we want to check whether a variable has a value or not, it is possible to use the empty() function.

34) How can we check the value of a given variable is alphanumeric?

It is possible to use the dedicated function, ctype_alnum to check whether it is an alphanumeric value or not.

35) How can we check the value of a given variable is a number?

It is possible to use the dedicated function, is_numeric() to check whether it is a number or not.

36) How can we access the data sent through the URL with the GET method?

To access the data sent via the GET method, we use $_GET array like this:www.url.com?var=value

$variable = $_GET["var"]; this will now contain 'value'

37) How can we access the data sent through the URL with the POST method?

To access the data sent this way, you use the $_POST array.

Imagine you have a form field called 'var' on the form when the user clicks submit to the post form, you can then access the value like this:

$_POST["var"];

38) How is it possible to know the number of rows returned in the result set?

The function mysqli_num_rows() returns the number of rows in a result set.

39) Which function gives us the number of affected entries by a query?

mysqli_affected_rows() return the number of entries affected by an SQL query.

40) What is the difference between mysqli_fetch_object() and mysqli_fetch_array()?

The mysqli_fetch_object() function collects the first single matching record where mysqli_fetch_array() collects all matching records from the table in an array.