It is planned to develop a messenger that stores all information on a server (later cluster/cloud of servers). The amount of messages is significant and exceeds the amount of table rows permitted by MySQL. Apparently there is no perfect solution, but a small number of good solutions. We want to find such a good solution and prevent the building of a legacy with a bad solution. Which is why we would like to receive EXPERT ADVICE on the various possible databases and an insight about their advantages and disadvantages with regards to this specific application. Your task will be to produce a summary with references and including information on the available databases, their advantages and disadvantages and their suitable for the application of a very large messenger.