This is sqlite3 running in your browser with a backend that properly persists the database in IndexedDB (absurd-sql). It stores each page from the db as a separate item, treating IDB like a hard disk. It never has to load the full DB into memory and can update it with small individual writes.
The below examples are meant to be stress tests, showing that it can handle large amounts of data and queries that need to scan all of it. With more normal cases and a small cache, it works really well. It easily beats IndexedDB up to a factor of 10.
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Backend:
Cache size: Using a cache will greatly improve perf, but no cache shows the full number of read/writes
Page size:
timings