n8n Workflow: Track Web Table Changes in Google Sheets

Automatically detect web table changes and log them in Google Sheets

This n8n workflow runs every morning to scrape an HTML table from a web page with Gaffa, sync it to your Google Sheets “Table” tab, and writes an audit trail of additions, changes, and removals into a “Changes” tab—complete with timestamps and field-level before/after details for updates.

What this workflow does

• Scheduled run: Executes every morning on a schedule.
• Scrape with Gaffa: Loads the configured page and extracts the target HTML table into structured rows.
• Fail fast on bad input: Stops with an error if the table can’t be read or if no rows contain the configured key column.
• Normalize and filter: Keeps only rows where the key column has a value.
• Compare current vs. stored data: Reads existing rows from Google Sheets “Table” (excluding rows already marked as removed) and detects:
  • New entries
  • Changed entries (using the key column)
  • Removed entries (rows missing from the latest scrape)
• Update Google Sheets: Appends new rows with first_seen and last_changed, updates changed rows in place (refreshing last_changed), and marks removals by setting removed_on.
• Write an audit log: Adds a change-log entry to the “Changes” tab for each addition, change (including field-level before/after), and removal.

Use cases

• Track updates to publicly available tables (releases, pricing lists, rosters, status pages) and maintain an up-to-date dataset in Google Sheets.
• Monitor competitor or partner webpages and capture a daily history of what changed.
• Provide SaaS ops teams a lightweight change tracking trail for spreadsheet-based reporting.

Technical details

• Gaffa node: Uses the community node @gaffa-dev/n8n-nodes-gaffa with a Gaffa API credential to extract the HTML table.
• Google Sheets: Creates/uses tabs matching your settings (default “Table” and “Changes”).
• n8n logic nodes: Includes if, set, filter, http request, and workflow notes (sticky note) to control scraping, validation, and synchronization behavior.