connect two databases for joint query?

[watersoft123]

This js sqlite tool is very nice, but it's a pity that few people pay attention to it. I have a question: how to connect two databases for joint query at the same time? I have stored two db in a memory database similar to localStorage, which can be accessed offline through setItem and getItem. This in-memory database can store large files, and even if the browser is cleared, it is not easy to lose them. I have saved two database files of nearly 100MB each.

lf-storage.txt