Write some aliases and identifiers to create/read/update/delete and then add save to external file when you edit the hash table with those aliases, typically you would want to start the system using a mIRC event like:
In that alias you would create then load your saved data from the .hsh file you saved before. Use more events to backup the system automatically too like exit disconnect depending on the data you are keeping. Then for your needs use the $hfind() to search and then $hget() identifier to retrieve , /help hash tables
I made something like this nearly 20 years ago, and it still works now. Updating it now.