Recommended way to handle write conflicts inside transactions?

Working with Data
3

Thanks for the reply, it’s true that before introducing transactions, concurrent updates on the same document worked without problems, however it looks like I’m running into the following issue:

https://docs.mongodb.com/manual/core/transactions-production-consideration/#in-progress-transactions-and-write-conflicts.

If a transaction is in progress and a write outside the transaction modifies a document that an operation in the transaction later tries to modify, the transaction aborts because of a write conflict

I’m not sure how to handle this case, since I might have dozens of concurrent transactions writing to the same document.

This is an example that produces write conflicts if run in parallel:

Query query = new Query();
query.addCriteria(Criteria.where("conversationId").is(conversation.getId()));
query.addCriteria(Criteria.where("ownerId").is(receiver.getId()));

Update update = new Update();
update.inc("unreadCount", 1);

mongoTemplate.updateFirst(query, update, Contact.class);
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