# WAL (The Sequential Diary) The **Write-Ahead Log (WAL)** is the sequential diary of everything that has ever happened in the Elephant Cafe. It is the absolute record of truth. No order is considered "cooked" until it is written in this diary. Unlike Data Files, which are scattered throughout the filing cabinet, the WAL is written sequentially. However, it still requires the elevator to go to the Frozen Pantry basement. ### Writing to the Diary ![[WALWrite]] ![[WALSync]] ![[WALInsert]] ### Initializing the Pages ![[WALInitWrite]] ![[WALInitSync]] ![[WALBootstrapWrite]] ![[WALBootstrapSync]] ### Managing the Log ![[WALCopyRead]] ![[WALCopyWrite]] ![[WALCopySync]] ![[WALRead]] ![[WALSyncMethodAssign]] ![[WALSenderTimelineHistoryRead]]