Which level of transaction isolation provides the highest degree of protection against conflicts?

The highest level of protection against conflicts is provided by the transaction isolation level Serializable.

The Serializable level guarantees that the result of executing multiple concurrent transactions will be the same as if they were executed sequentially, one after the other. This prevents issues such as phantom reads, non-repeatable reads, and dirty reads.

Examples of isolation levels (from lower to higher protection):

• Read Uncommitted
• Read Committed
• Repeatable Read
• Serializable

Using Serializable reduces the likelihood of conflicts and ensures maximum data integrity, but may impact performance due to locking and waiting.