How does MySQL handle concurrent inserts?

Question

I know there is one issue in MySQL with concurrent SELECT and INSERT. However, my question is if I open up two connections with MySQL and keep loading data using both of them, does MySQL takes data concurrently or waits for one to finish before loading another?

I’d like to know how MySQL behaves in both cases. Like when I am trying to load data in the same table or different tables concurrently when opening separate connections.

question from:https://stackoverflow.com/questions/32087233/how-does-mysql-handle-concurrent-inserts

Answer 1

If you will create a new connection to the database and perform inserts from both the links, then from the database's perspective, it will still be sequential.

The documentation of Concurrent Inserts on the MySQL's documentation page says:

If there are multiple INSERT statements, they are queued and performed in sequence, concurrently with the SELECT statements.

Mind that there is no control over the order in which two concurrent inserts will take place. The order in this concurrency is at the mercy of a lot of different factors. To ensure order, by default you will have to sacrifice concurrency.