AL Table Visualizer

A Visual Studio Code extension that parses Business Central AL source files and compiled .app symbol packages to render an interactive ER-style diagram of table relationships.

Screenshots

Interactive ER diagram showing all table relationships in the workspace

Focus the diagram on the table in the active editor

Sortable Related Tables list panel with By Table / By Relation toggle and hop distance badges

Browse and visualize relationships including standard Business Central base app tables

Features

Diagram

• ER diagram — entity boxes with field names and data types, crow's foot notation on relation edges
• Focus mode — double-click any table to expand its neighbourhood; the depth slider controls how many hops to show (max configurable to 10)
• Filter by name — type in the search box to narrow the diagram to matching tables
• Project filter — choose a workspace folder from the Project dropdown to restrict the default view to tables from that project only; useful when multiple AL apps share a workspace
• App Package filter — choose an app package (e.g. Microsoft / Base Application 25.0.0.0) from the App Package dropdown to browse its tables and see which source tables reference them
• Namespace mode — choose a namespace prefix from the Namespace dropdown to see all tables in that namespace and their neighbours
• Direction toggle — switch between Out (following FKs that leave the focused table), In (FKs that arrive at it), or Both directions
• Back / Forward navigation — use the ‹/› buttons to move through the focus history within a session
• BFS-ranked node cap — when the diagram exceeds the configured node limit the closest tables survive; a notice shows the total count and how to raise the limit
• Colour themes — switch between Dark, Light, High Contrast and Solarized palettes; the choice is persisted to settings

Export

• PNG / SVG — export the current diagram view as an image
• Mermaid — copy a Mermaid ER diagram definition to the clipboard; collision-safe identifier names are generated automatically
• CSV — export the Related Tables list as a CSV file

Related Tables list panel

• Opens alongside the diagram via the 🔗 Related button or Find Related Tables command
• By Table view — one row per reachable table with minimum hop distance, total relation count, and a direct annotation
• By Relation view — field-level detail showing every source/target field pair
• Direction badge — shows whether the current list covers Out, In, or Both directions
• Sort — click any column header to sort; click again to reverse
• Filter — type to filter by table or field name within the current view
• Pagination — large result sets are shown in pages of 100 rows
• Click to navigate — clicking a table name focuses the diagram and opens the source file

Source & packages

• Open source — right-click a diagram node or click a name in the list to jump to its .al declaration; works for both local files and tables from .app packages
• Base-app coverage — reads compiled .app symbol packages so relations to standard BC tables resolve correctly; publisher/name/version identity is read from app.json inside the ZIP
• Deduplication across projects — when multiple workspace folders each have the same .app in their .alpackages/ folder, the scanner detects identical content (SHA-256) and parses it only once; shared packages are also stored as a single cache entry
• Incremental rescan — when an .al file changes only that file is re-parsed; the rest of the graph is preserved
• Enum field labels — fields declared as Enum "Name" show the enum type name rather than a numeric ID
• CASE/WHEN relations — multi-branch TableRelation values using CASE … OF … WHEN are fully parsed

Workspace integration

• Live refresh — diagram updates automatically when .al files are saved
• Manual re-scan — run AL Table Viz: Re-scan Workspace to force a full rescan and clear all caches

Commands

Configuration

Requirements

• VS Code 1.85+
• An AL workspace with .al source files (AL Language extension recommended)
• Compiled .app symbol packages for base-app table coverage (place them anywhere in the workspace)

Development

npm install
npm run compile    # single build
npm run watch      # rebuild on change
npm test           # run unit tests (parser + graph, no VS Code host required)

Press F5 in VS Code to launch the Extension Development Host.

Architecture