What are the typical problems and failures that can occur when executing multiple transactions simultaneously in a system?

When executing multiple transactions simultaneously in a system, the following typical problems and failures may occur:

• Race conditions: when several transactions try to modify the same data at the same time, leading to unpredictable results.
• Deadlocks: a situation where two or more transactions are waiting for resources held by each other, and none can proceed.
• Isolation violations: reading "dirty" data, non-repeatable reads, or phantom reads, which lead to inconsistency.
• Lost updates: when changes made by one transaction are overwritten by another without consideration.

To prevent these issues, mechanisms such as:

• Transaction isolation levels (Read Uncommitted, Read Committed, Repeatable Read, Serializable).
• Locks at the row, table, or object level.
• Timeouts and deadlock detection and resolution algorithms.

In Go, when working with databases and concurrent processes, it is important to use transactions and synchronization (e.g., mutex) to avoid such problems.