v21.1.2
Fixes SQLITE_BUSY errors caused by the shift to IMMEDIATE transactions.
Updating the transaction type from the default DEFERRED to IMMEDIATE exposed some issues with the way SQLite wrapped GRDB. SQLite was wrapping some writes in an unnecessary transaction. This caused issues because IMMEDIATE transactions immediately begin a write, meaning other writes will receive a SQLITE_BUSY error. Before applying the changes in this release, vacuuming and checkpointing tests failed when IMMEDIATE transactions were used.