Compare selected row data between two databases with the same schema, inspect the generated SQL, and choose when to apply it. ReconcileDB is local-first: database connections and generated files stay on your machine.

Thank you, Nguyen Ngoc Long. ReconcileDB for VS Code is an independently maintained fork of Data Sync, originally created by Nguyen Ngoc Long. His work made this extension possible. The upstream copyright and MIT license are preserved in LICENSE. This project is not affiliated with or endorsed by the original maintainer.

The comparison view puts the decision-making details together before you run a migration:

1. Select a table under Compare to see insert, update, and delete counts. Filter by operation or search for a row by its key or changed column.
2. Select a row to see only its changed fields, with target (before) and source (after) values side by side. Switch to a unified diff when that is easier to read.
3. For a long text field, switch its view from Raw text to Pretty JSON, Pretty HTML, or Rendered HTML. JSON and HTML suggestions help you find a useful view, but the choice stays yours.
4. Expand Exact source and target values whenever you need to inspect the original data, then review the generated migration SQL before applying anything.

These screenshots show the actual comparison view with fictional sample data:

Pretty JSON: line-level changes in a structured text column, alongside the row list and change filters.

Rendered HTML: isolated before-and-after previews of an HTML text column.

Field diffs use Pierre Diffs. The row list stays compact, and full field values are loaded only for the row you select. Formatting runs on demand, so large JSON or HTML columns do not need to be prettified just to browse the results.

The rendered HTML view is an isolated visual preview: it omits scripts, navigation, forms, images, and external styles. Views are display-only—comparison and migration always use the exact stored values. Values over 2 MB remain available in Raw text instead of being formatted or previewed.

• Compares row data from PostgreSQL to PostgreSQL or SQL Server to SQL Server.
• Lets you select tables and columns, exclude volatile columns, filter rows, and define stable ordering or primary keys.
• Opens a row-first comparison review with operation filters, primary-key search, changed-column summaries, and field-level source/target values.
• Loads large field values only when their row is selected, renders them with Pierre Diffs, and keeps the original JSONL diff available as a fallback.
• Offers per-field Pretty JSON, Pretty HTML, and isolated HTML previews while retaining the exact stored values for comparison and migration.
• Shows the generated migration plan before anything is applied.
• Generates inserts, updates, and deletes that can be individually disabled.
• Applies migrations in a transaction and reports suspicious row counts.
• Uses exact value comparison. ReconcileDB does not silently normalize text, timestamps, or numbers.

ReconcileDB 1.1.x does not compare or migrate database schemas, perform cross-engine synchronization, or run as a VS Code web extension.

Install ReconcileDB for VS Code from the Visual Studio Marketplace or Open VSX Registry.

The universal desktop package supports PostgreSQL and SQL Server username/password authentication on Windows, macOS, and Linux.

1. Open the ReconcileDB activity-bar view.
2. Choose Generate Configuration File.
3. Configure a source and target of the same database engine.
4. Select the tables, keys, and columns to compare.
5. Run Analyze Data, select a table under Compare to review changed rows and fields, inspect the migration SQL, then explicitly choose whether to execute it.

The existing data-sync.* command IDs, settings, and database.json format remain compatible with the original extension so existing local configurations can be reused.

{
  "verbose": false,
  "patterns": {
    "staging-to-local": {
      "source": {
        "type": "postgres",
        "host": "staging.example.test",
        "port": 5432,
        "database": "app",
        "user": "reconciler"
      },
      "target": {
        "type": "postgres",
        "host": "localhost",
        "port": 5432,
        "database": "app",
        "user": "postgres"
      },
      "diff": {
        "tables": [
          {
            "schema": "public",
            "name": "customers",
            "primaryKeys": ["id"],
            "excludes": ["updated_at"],
            "orderBy": "id"
          }
        ]
      },
      "migrate": {
        "noInsert": false,
        "noUpdate": false,
        "noDelete": false,
        "noRowAffected": "warn",
        "multipleRowAffected": "throw"
      }
    }
  }
}

For SQL Server authentication, use the same structure with "type": "mssql", normally on port 1433:

{
  "type": "mssql",
  "host": "localhost",
  "port": 1433,
  "database": "app",
  "user": "reconciler"
}

When the password property is omitted, ReconcileDB prompts for it. Username/password connection strings are also supported.

• Windows integrated authentication. This would require revisiting native-driver packaging; for now, use SQL Server username/password authentication.

• Review generated migration SQL before execution, especially deletes.
• Use a least-privilege database account and test against disposable data first.
• Put secrets in a local configuration ignored by source control. If password is omitted, the extension can prompt for it.
• Define primaryKeys or a deterministic orderBy for tables without discoverable primary keys.
• Exclude columns such as generated timestamps, row versions, audit metadata, or environment-specific identifiers when they are intentionally different.

Please report bugs and feature requests in the JCofman/vs-data-sync issue tracker.

ReconcileDB for VS Code is distributed under the MIT License.

Field-level diff rendering uses @pierre/diffs, distributed under the Apache License 2.0. Its license is included in packaged extensions. HTML presentation uses Prettier, distributed under the MIT License. Its license is also included in packaged extensions. Rendered HTML previews use DOMPurify under the Apache 2.0 License, which is included in packaged extensions.