Generating a unique string

Generating unique string: uniqid()

If you need to generate a unique string, you may use the uniqid() function.

It is not a random generation function. It returns a timestamp with microseconds in string format.

You can prefix a string to distinguish your unique values.

$id = uniqid(); // 6187f27185e08

The function uniqid() with prefix

$id = uniqid("cache_"); // cache_6187f299640ff

The function uniqid() with prefix adds more entropy:

$id = uniqid("cache_", true); // cache_6187f2ebbb2ba7.06827816