Many developers use md5 or rand() function to generate the unique id in php, Which is actually not a good practice under some senario. The best technique is to use the pre given php function whic is uniqid()
Example:
// generate unique string echo uniqid(); /* prints 4bd67c947233e */ // generate another unique string echo uniqid(); /* prints 4bd67c9472340 */
// with prefix echo uniqid('ilovephp_'); /* prints ilovephp_4bd67d6cd8b8f */ // with more entropy echo uniqid('',true); /* prints 4bd67d6cd8b926.12135106 */ // both echo uniqid('phpfresher_',true); /* prints phpfresher_4bd67da367b650.43684647 */
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