In DB2, a shared lock allows ________ transactions to read data but prevents them from modifying it.

A shared lock in DB2 allows multiple transactions to read data simultaneously. However, it prevents them from modifying it concurrently. This ensures that multiple transactions can access the data for reading purposes without interfering with each other's modifications, promoting data consistency and integrity in a multi-user environment. Shared locks are commonly used to facilitate data retrieval operations without the risk of conflicting modifications by other transactions.