Posts tagged "backend"

When two systems edit the same record, last-write-wins is the easy answer. It also throws away data on purpose. Here is when that is fine, and when it is a trap.

When you really delete a row, other systems can never learn that it is gone. A tombstone is a delete you can see. Here is why it matters and how to use one.

Offset pagination is easy to write and breaks in two ways: it gets slow, and it skips or repeats rows when the data changes. Cursor pagination fixes both. Here is the difference.

Everybody wants exactly-once delivery. Over a network it is impossible. Here is why, and the trick that gives you the same result in practice.

A request times out, you retry, and now the customer is charged two times. An idempotency key is the small idea that makes retries safe. Here is what it is and how to build one.