Isolation level

The LN MSQL driver uses the read uncommitted isolation level, which means that (multi-row) read requests do not acquire any type of lock (shared or exclusive) unless explicitly stated in the query syntax. Queries such as INSERT, DELETE, and UPDATE acquire an exclusive lock implicitly. A SELECT WITH LOCK request acquires an update lock. Only in case of lookup references are shared locks acquired. The locks are retained until the transaction is committed or aborted.