Explain include(), include_once, require() and require_once.

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Correct Answer: A session is a logical object created by the PHP engine to allow you to preserve data across subsequent HTTP requests Sessions are commonly used to store temporary data to allow multiple PHP pages to offer a complete functional transaction for the same visitor

Correct Answer: On the server side, the main difference between GET and POST is where the submitted is stored The $_GET array stores data submitted by the GET method The $_POST array stores data submitted by the POST method On the browser side, the difference is that data submitted by the GET method will be displayed in the browser?s address field Data submitted by the POST method will not be displayed anywhere on the browser GET method is mostly used for submitting a small amount and less sensitive data POST method is mostly used for submitting a large amount or sensitive data

Correct Answer: Calculate the md5 hash of a string The hash is a 32-character hexadecimal number I use it to generate keys which I use to identify users etc If I add random no techniques to it the md5 generated now will be totally different for the same string I am using

Correct Answer: $result = mysql_query($sql, $db_link); $num_rows = mysql_num_rows($result); echo "$num_rows rows found";

Correct Answer: We can use the preg_match() function with ?/*@(*)$/? as the regular expression pattern For example: preg_match("/*@(*)$/","https://info@abccom",$data); echo $data[1]; ?>

Correct Answer: Notices: These are trivial, non-critical errors that PHP encounters while executing a script - for example, accessing a variable that has not yet been defined By default, such errors are not displayed to the user at all - although, as you will see, you can change this default behaviour Warnings: These are more serious errors - for example, attempting to include() a file which does not exist By default, these errors are displayed to the user, but they do not result in script termination Fatal errors: These are critical errors - for example, instantiating an object of a non-existent class, or calling a non-existent function These errors cause the immediate termination of the script, and PHP?s default behaviour is to display them to the user when they take place

Correct Answer: strstr() returns part of a given string from the first occurrence of a given substring to the end of the string For example: strstr("user@examplecom","@") will return "@examplecom" stristr() is idential to strstr() except that it is case insensitive

Correct Answer: mysql_fetch_array: Fetch a result row as an associative array and a numeric array mysql_fetch_object: Returns an object with properties that correspond to the fetched row and moves the internal data pointer ahead Returns an object with properties that correspond to the fetched row, or FALSE if there are no more rows mysql_fetch_row(): Fetches one row of data from the result associated with the specified result identifier The row is returned as an array Each result column is stored in an array offset, starting at offset 0

Correct Answer: CRYPT(), MD5()