How to Generate a Unique ID in PHP

How to Generate a Unique ID in PHP A unique user ID can be created in PHP using the uniqid () function. This function has two parameters  you can set. The first is the prefix, which is what will be appended to the beginning of each ID. The second is more_entropy. If this is false or not specified, it will return 13 characters; if its  true, 23 characters will be returned. Examples For Creating a Unique ID Below are examples of creating a unique user ID, but each are a little different. The first creates a normal unique ID while the second shows how to make a longer ID. The third example creates an ID with a random number as the prefix while the last line can be used to encrypt the username before storing it. //creates a unique id with the about prefix $a uniqid(about); echo $a; echo br; //creates a longer unique id with the about prefix $b uniqid (about, true); Echo $b; echo br; //creates a unique ID with a random number as a prefix - more secure than a static prefix $c uniqid (rand (),true); echo $c; echo br; //this md5 encrypts the username from above, so its ready to be stored in your database $md5c md5($c); echo $md5c; ?