After installing PHP on Apache you can use the php.ini file to set various different options to do with PHP. When Apache starts it uses what is contained in this file to set up and run PHP.
On both Windows, Unix and Linux systems Apache will look in a number of default locations for the php.ini file before giving up. You can explicitly tell Apache 2.x where to look for the file by using the PHPIniDir directive in the http.conf file.
All of the maths functions in JavaScript are kept in a handy object called Math, which contains a number of different functions.
To get the absolute value of a number use the abs() function.
Math.abs(3.14159265) // returns 3.14159265
Rounding a number is done by either the round() function to round to the nearest integer, the ceil() function to round up to the nearest integer and the floor() function to round down to the nearest integer.
To redirect the current page to a different location you use the header() function in the following way:
When printing off source code there is a handy function that will parse the code and produce nice looking syntax highlighted code. There are actually two functions you can use. The highlight_string() function takes a string as a parameter and will print the highlighted code. The highlight_file() function takes a file name as a parameter, the contents of which are printed off with highlighted syntax. For now I will concentrate on the highlight_string() function, but the output of these two functions is the same.
To set up multiple Google Analytics tags on the same page you need to use the _uff = false; command in between the unchinTracker() calls to reset the tracker for the next account. The urchinTracker() function will send information on the page visit off to Google Analytics.
To get a random row from a PostgreSQL database you need to use the RANDOM() function. This is similar to the MySQL function RAND() and will generate a new random number for each row and order them by that new number. This is used in conjunction with the LIMIT clause to limit the amount of returned rows to one.
SELECT value FROM table ORDER BY RANDOM() LIMIT 1If you are querying a database you should get into the habit of sanitising your input, even if it's not coming from users at the moment it might do in the future. SQL injection attacks are all too common and they can be easily prevented.
To get a random row from a Microsoft SQL database you need to use the NEWID() function. This will generate a new random number for each row and order them by that new number. This is used in conjunction with the TOP clause to limit the amount of returned rows to one.
Those of you who have coded in PHP must have looked at the PHP website at some point, even if it was just to down load the latest version, or to look up a function reference.
What most people don't realise is that there is a really easy way to go straight to the page that you want without having to mess around with the tetchy search engine on the PHP site.
The following mode function will return the most commonly occurring value from an array of values, also called the mode. If just the array is used then only the most commonly occurring value will be returned. The second parameter can be used to return an array containing the mode and the number of times that this value occurs in the array.