Sequential number stamp generator, no repeats
A sequential number stamp generator with a server-held counter incremented under a row lock, so no two impressions can carry the same number.
Printing a number on a stamp is easy and every tool can do it. Guaranteeing that the number is never issued twice is the hard part, and it is the only part that makes a numbered impression worth anything.
What you get
- Each saved stamp gets its own counter, so registers do not share a sequence.
- Incremented under a database row lock: two tabs, two devices or two people cannot collide.
- Survives a cleared browser and a new machine, because it is not stored locally.
- Zero padding and a prefix, so 000042 and CTC-000042 sort and read correctly.
- Only ever goes up. A counter that can be reset is one that can reissue.
How to make it
- Open the stamp maker and pick a shape, or start from a template.
- Type your wording, then set the colour, border and size.
- Add the date, time, serial number or logo, and position each one.
- Preview it live, then download. Designing and previewing are free.
Questions
How is this different from typing the number in?
A typed number is whatever you remembered to type. A counter is incremented by the server as part of issuing the file, so it cannot skip, repeat or depend on anyone paying attention.
Can two people share one numbering stamp?
Yes, and that is the case this is built for. Both draw from the same sequence, and the row lock means simultaneous requests are queued rather than duplicated.
What happens if I clear my browser data?
Nothing. The counter is on the server against the saved stamp, not in your browser, which is the difference between this and a local counter.
Can I set the starting number?
You can set a prefix and the padding width. The sequence itself starts at one and only increases, because a resettable counter reissues numbers and a reissued serial is worse than none.