Script to generate a unique ID based on date
First 14 characters are based on the current time stamp in format YYYYMMDDHHMMSS, followed by an underscore and a random set of four alphanumeric characters. I'm not sure how likely this method is to generate duplicate IDs, but would guess quite unlikely. For a quick test, generated 5K four character sets and saw zero duplicates, so I think the chances of duplicates generated within one second are very low, unless /dev/urandom on your system is not very random.
#!/bin/bash date=$(date +%Y%m%d%H%M%S) rand=$(cat /dev/urandom | tr -cd [:alnum:] | head -c 4) ID=$date"_"$rand