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Import Existing Metadata

If you already have databases with tables, views, and schemas defined, you don’t have to recreate everything by hand in ADL. The Metadata Importer lets you bring in existing structure and load it into your project.

When to use the importer

Section titled “When to use the importer”

The Metadata Importer is useful when:

  • Starting a new project with an existing database — import the current schema so you don’t have to define every table and column manually.
  • Adding a source system — Bring in the structure of a source database that you’ll be mapping data from.
  • Keeping metadata in sync — Re-import to pick up schema changes made outside of ADL.

How it works

Section titled “How it works”

The import process has two parts:

  1. Extract metadata from your database using a SQL query or JSON file.
  2. Load the metadata into ADL through the Metadata Importer screen.

Extracting metadata with SQL

Section titled “Extracting metadata with SQL”

ADL provides sample SQL queries that extract metadata from your database in the format ADL expects. You run these queries against your database, and the results can be saved as JSON and imported into ADL.

Sample queries are available for:

  • Connections — Extract database and schema information.
  • Data Objects — Extract table and view definitions, including columns, data types, and keys.

You can find these sample queries in the Metadata Importer section of the documentation.

Importing from JSON

Section titled “Importing from JSON”

If you already have metadata in JSON format (perhaps from another tool or a custom export), you can import it directly. The JSON should follow the Generation Metadata Schema format used by ADL.

Step by step

Section titled “Step by step”
  1. Run the extraction query against your source database and save the results as a JSON file.
  2. Navigate to the Metadata Importer in the ADL app.
  3. Select your JSON file and review the metadata that will be imported.
  4. Import — ADL creates the corresponding data connections, data objects, and data items in your project.
  5. Review — Check the imported objects on the Data Objects and Connections screens to make sure everything looks right.

Tips

Section titled “Tips”
  • Import into a fresh project to avoid conflicts with existing metadata.
  • Review after importing — The import creates the basic structure, but you may want to add business keys, classifications, or extensions that aren’t captured in the source database schema.
  • Use the Graph — After importing, the Graph view is a great way to see all your imported objects and their relationships at a glance.
  • Customize the SQL queries — The sample queries are a starting point. You can modify them to extract additional metadata or filter to specific schemas/tables.

What’s next?

Section titled “What’s next?”