Note this utility is used to feed to an ETL that moves AirTable data into SQL. (In my case Postgresql.) I'll be making that code public soon. Contact me if you need it sooner.

Airtable Schema Reader

A .NET utility that reads and displays the complete schema of an Airtable base, including all tables, fields, and data types.

Purpose

This tool helps you understand the structure of your Airtable base before migrating data to PostgreSQL. It will show you:

• All tables in your base
• All fields (columns) in each table
• Field types and configurations
• Field options (choices for select fields, formulas, etc.)

Prerequisites

• .NET 10.0 SDK
• Airtable API key (Personal Access Token)
• Airtable Base ID

Configuration

Update appsettings.json with your Airtable credentials:

{
  "Airtable": {
    "ApiKey": "YOUR_AIRTABLE_API_KEY",
    "BaseId": "YOUR_BASE_ID"
  }
}

Getting Your Credentials

1. API Key: Create a Personal Access Token at https://airtable.com/create/tokens

   • Give it a name (e.g., "Schema Reader")
   • Add scopes: schema.bases:read
   • Add access to your base

2. Base ID: Found in your Airtable API documentation

   • Go to https://airtable.com/api
   • Select your base
   • The Base ID looks like appXXXXXXXXXXXXXX

Usage

cd AirtableSchemaReader
dotnet run

For the full list of options, run dotnet run -- --help (also accepts -h, -?, /?, ?).

Schema Overrides

You can customize the output without modifying source code using schema_overrides.json. This is useful for making the exported schema match what the ETL expects (e.g. excluding redundant lookup fields, overriding field types).

Supported actions: exclude, setType, rename, setOptions, add

See SCHEMA_OVERRIDES.md for full documentation.

Output

The tool will:

1. Apply any overrides from schema_overrides.json (if present)
2. Display the schema in the console with formatted tables
3. Save a detailed schema report to airtable_schema.txt

Console Output Example

================================================================================
AIRTABLE SCHEMA READER
================================================================================
Base ID: appXXXXXXXXXXXXXX

Fetching schema from Airtable...
Found 2 table(s) in this base:

================================================================================
TABLE: Customers
ID: tblXXXXXXXXXXXXXX
================================================================================

  Field Name                     Field Type           Description
  ------------------------------ -------------------- ------------------------------
  Name                           singleLineText
  Email                          email
  Status                         singleSelect
      Choices: Active, Inactive, Pending
  Created Date                   date

File Output

The airtable_schema.txt file contains the same information with additional details like field IDs and full options JSON.

Supported Field Types

The tool recognizes all Airtable field types including:

• Text fields (singleLineText, multilineText, email, url, etc.)
• Number fields (number, currency, percent, rating)
• Date/time fields
• Select fields (singleSelect, multipleSelects)
• Checkbox and other boolean fields
• Attachment fields
• Linked records
• Formula fields
• Rollup and Lookup fields
• And more...

Next Steps

After running this tool:

1. Review the airtable_schema.txt file
2. Use this information to design your PostgreSQL schema
3. Update the AirtableToPostgres project with the proper field mappings

Troubleshooting

Error: "Failed to fetch schema: 401"

• Your API key is invalid or expired
• Create a new Personal Access Token with schema.bases:read scope

Error: "Failed to fetch schema: 403"

• Your token doesn't have permission to access this base
• Add the base to your token's access list

Error: "Failed to fetch schema: 404"

• The Base ID is incorrect
• Verify the Base ID from your Airtable API documentation