System.Data.SQLite in a multithreading database

Question

I am creating a System.Data.SQLite database in memory using the connection string as

"Data Source=:memory:", 

and want to access this database from multiple threads.

Now I have to clone the SQLiteConnection object and pass the copy to the worker threads.

But I found that different threads actually receive separate database instances in memory, not shared ones. How can I share a single database in memory among threads?

Thanks!

Answer 1

Based on the SQLite documentation for in-memory databases, I would try to use a data source called URI filename convention file::memory:?cache=shared or the like from :memory: (and pay attention, in particular, to the cache name, which all connections say use). As explained on the page, each instance of :memory: is different from each other, just like you found.

Note that you also need to enable shared cache mode first before establishing connections to the database in memory (as indicated in the shared cache documentation calling sqlite3_enable_shared_cache(int) for this.