chickadee » sqdb » with-transaction

with-transaction db thunk #!optional (type deferred)procedure

Executes thunk inside an atomic transaction. If thunk raises an exception or returns #f, the transaction is rolled back. Otherwise it is committed when thunk exits.

Warning: transactions may not be nested. An error will occur if you try.

type may be

deferred
Everyone can write until our first read or write; everyone can read until our first write.
immediate
No one else can write, but everyone can read until our first write.
exclusive
No one else can read or write.