More seriously, the "will considerably slow down" part is a common trope. Basically same argument as in HTTP versus HTTPS, but vast majority of websites are now on HTTPS, and the people who continue to run their sites on HTTP aren't doing it because encryption considerably slows down their traffic.
I beg to differ, if you have a few hundred GB database with large blobs fields, encryption will slow down the application, I experienced firsthand.
Obviously I have no idea what's in your database, but just going by your statement, some thoughts come to mind, assuming you're talking about SQLite with encryption in the context of a single-user GUI application:
-
https://sqlite.org/intern-v-extern-blob.html (of course this loses the transparent encryption)
- sharding the database over multiple files, and using ATTACH (perhaps with
UNION virtual table), or simply multiple database connections to process the relevant database file
Personally, "encryption causes slow down" is never a reason to not use encryption. If you gotta do it, you gotta do it.
The reason to not use encryption is when it is unnecessary.