Home › Formats › .SQLite-SHMID
What is a .SQLite-SHM file?
A .sqlite-shm file is the shared-memory index that lets several processes navigate a SQLite write-ahead log at the same time, mapping WAL frames to database pages. Written by SQLite alongside the -wal file.
- Did you know
- The -shm file holds no real data of its own - it is a rebuildable index over the -wal log, and SQLite recreates it from scratch if it is missing.
- The -shm file is normally memory-mapped, letting several processes on one machine share a single view of the write-ahead log.
- It stores its numbers in the host computer native byte order, because it is only ever used locally and never copied between machines.
- It keeps two copies of its header and compares them, so a torn write during an update can be spotted and repaired.
- What Analyser reads
- Open SQLite databases (.sqlite/.db/.sqlite3) and read their full schema in-browser - every table with its columns and row counts, views, indexes, triggers, the CREATE-statement DDL, and a sample of the largest table. Reads the WAL-mode sidecars too: the Write-Ahead Log (-wal) - page size, salts, frame and committed-transaction counts, and the pages it changed - and the shared-memory index (-shm) - valid frame count, database size and checkpoint progress. Also parses .sql dumps (dialect, tables, columns, INSERT counts) and identifies Microsoft Access (MDB, ACCDB).
- Depth of analysis
- .SQLite-SHM is an identification-grade format: Analyser recognises it from its bytes and decodes the header metadata it carries, rather than opening it in a full viewer. Formats that do get a full viewer are marked "Full" on the formats page.
- Open a .SQLite-SHM file
- Drag a .SQLite-SHM file onto the Analyser home page (or tap to pick one). It is identified entirely in your browser - nothing is uploaded, there is no account, and it works offline once installed.