- **Description**: Handles insert, update, and delete operations. - **Performance**: Depends on type of modification (INSERT, UPDATE, DELETE). - **Factors**: Number of rows modified, indexes on the table. - **Cost**: `operation cost * number of rows` - ![[ex_insert.svg|200x200]] ![[ex_update.svg|200x200]] ![[ex_delete.svg|200x200]] - **Operates on**: [[Page]] [[Tuple]] - **Workloads**: - [[IO]] - [[DataFileWrite]] - [[DataFileExtend]] - [[DataFileSync]] - [[WALWrite]] - [[Lock]] - [[relation]] - [[tuple]] - [[transactionid]] - [[LWLock]] - [[WALInsert]] - [[BufferContent]] - [[BufferMapping]] - [[IPC]] - [[SyncRep]]