![[assets/ex_lockrows.png|256]] - **Description**: Locks rows without changing them. - **Performance**: Adds overhead due to locking. - **Factors**: Number of rows locked, lock contention. - **Cost**: `lock acquisition cost * number of rows` - ![[assets/ex_lock_rows.svg|200x200]] - **Operates on**: [[Structures/Page]][[Structures/Tuple]] - **Workloads**: - [[Workloads/Lock]] - [[Workloads/Sub/tuple]] - [[Workloads/Sub/transactionid]] - [[Workloads/LWLock]] - [[Workloads/Sub/LockManager]] - [[Workloads/IPC]] - [[Workloads/Sub/SafeSnapshot]]