Access database thread-related tests for transactions

One, in the transaction a thread (transaction), B thread
① the same connection operation is the same table, if the A-thread operation is rolled back, the operation of the B-thread is also rolled back
② the same connection operation two different tables, if the operation of a thread is rolled back, the operation of the B thread will also be rolled back
③ two different connections to the same database cannot operate on the same table (will cause a crash)
④ two different connection operations of the same database two different tables, if the operation of a thread is rolled back, the operation of the B thread will not be rolled back
⑤ main thread, using two different CRecordset operations created by the same connection in the transaction two tables, two table operations are rolled back if an exception occurs

⑥ main thread, two tables in a transaction using two different CRecordset created by different connections, the database operation for which the transaction connection was not started succeeds

Second, non-transactional (throws an exception in a)

① the same connection operation on the same table, the A-thread operation was unsuccessful (the operation succeeded before the exception was thrown), but the operation of the B-thread succeeded

Third, the database connection cannot be opened before the transaction starts

Just some of your own tests, not exactly what you can add.