Enum Synchronous 

#[non_exhaustive]
pub enum Synchronous {
    Full,
    Normal,
}

https://www.sqlite.org/pragma.html#pragma_synchronous

Note that the database uses WAL mode, so make sure to read the WAL specific section.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Full

SQLite will fsync after every transaction.

Transactions are durable, even following a power failure or hard reboot.

Normal

SQLite will only do essential fsync to prevent corruption.

The database will not rollback transactions due to application crashes, but it might rollback due to a hardware reset or power loss. Use this when performance is more important than durability.