Question

I was wondering how SQLite behaves when it’s given multiple databases to insert/update/delete in at the same time? Does it spawn multiple processes which can in theory have better concurrency than using a single database/single process or it utilizes the same process for each?

Searching through the documentation didn’t provide e with a definitive answer. I am aware that SQLite isn’t the most ideal environment for multiple writes, as the database resides in as single file. But does that mean that multiple files = different write processes?

databaseOne = connectToSqlite('databaseOne'); 
databaseTwo = connectToSqlite('databaseTwo');
function write()
    queryDatabaseOne("INSERT SOMETHING INTO SOME_TABLE VALUES SOME_VALUES");
    queryDatabaseTwo("INSERT SOMETHING INTO SOME_TABLE VALUES SOME_VALUES");

So, two different sqlite databases, and two inserts executed in parallel, towards tables in the two databases.

Thanks

Answer 1

Normally, database queries are blocking – they do not return until they are complete. This helps secure the integrity of the database. The SQLITE API is blocking.

Of course, if you have a multiple databases, then you can write a multi-threaded application with non-blocking routines that call the the SQLITE API and then code overlapping, parallel inserts to the multiple databases. You will have to be careful about all the usual things in a multithreaded application – the SQLITE API will neither help not hinder – with added complication of insuring that there in no possibility of overlapping accesses to the SAME database.