SQLite: Missing IMMEDIATE and EXCLUSIVE Transaction Functionality

[fpgaminer]

It does not appear that there is a way to start an IMMEDIATE or EXCLUSIVE transaction for a SQLite database. All Transactions are started using BEGIN, but SQLite supports BEGIN IMMEDIATE and BEGIN EXCLUSIVE. The former is of some import for simplifying some code I'm writing. It would allow me to catch SQLITE_BUSY and retry at the start of the transaction rather than having to catch it at any point throughout a sequence of queries and add complex replay logic.

I took a look at the codebase, but didn't see an easy way to add the functionality since Transaction is generic over databases and this would be a SQLite specific feature. Perhaps begin could have some kind of TransactionOptions parameter added that could toggle database specific features? To reduce API breakage a begin_with_options API could be added.

Thank you.

[abonander]

Duplicate of #481