Working with Data API Builder

In this blog post, we’ll explore how to work with the Data API Builder. Data API builder (DAB) provides a REST API over a database. It also provides a GraphQL API. It supports not just SQL Server, but Azure SQL Database, Azure Cosmos DB, PostgreSQL, MySQL, and SQL Data Warehouse. Long back I wrote a blog post about Getting started on Data API Builder. Now Data API builder support Azure SQL Database, Azure Cosmos DB, PostgreSQL, MySQL, and SQL Data Warehouse.

For this blog post I will be using Northwind database. I am running the SQL Server 2025 in my local machine using Docker. Here is the command to run SQL Server 2025 using Docker.

docker run \
    --env "ACCEPT_EULA=Y" \
    --env "MSSQL_SA_PASSWORD=<your-password>" \
    --publish 1433:1433 \
    --detach \
    mcr.microsoft.com/mssql/server:2025-latest

We can connect to SQL Server and restore the database. Next we need to install the Data API builder dotnet tool. We can do this using the following command dotnet tool install --global Microsoft.DataApiBuilder. Once it is installed, we can create the configuration file for Microsoft.DataApiBuilder. We can do this by running the command dab init --database-type "mssql" --host-mode "Development" --connection-string "Server=localhost,1433;User Id=sa;Database=Northwind;Password=<your-password>;TrustServerCertificate=True;Encrypt=True;". This will create a JSON file dab-config.json. This file contains various configuration settings like connection strings, security configuration etc.

Next we need to add the tables, stored procedures and views - to expose them as REST API. So for this blog post I am adding all the tables.

dab add Employees --source "dbo.Employees" --permissions "anonymous:*"
dab add Categories --source "dbo.Categories" --permissions "anonymous:*"
dab add Customers --source "dbo.Customers" --permissions "anonymous:*"
dab add Shippers --source "dbo.Shippers" --permissions "anonymous:*"
dab add Suppliers --source "dbo.Suppliers" --permissions "anonymous:*"
dab add Orders --source "dbo.Orders" --permissions "anonymous:*"   
dab add Products --source "dbo.Products" --permissions "anonymous:*"
dab add OrderDetails --source "dbo.Order Details" --permissions "anonymous:*"  

In the above commands, I am adding all the tables in Data ApiBuilder. For this demo I am keeping the permissions as anonymous, we can configure it Azure Entra ID or other security mechanisms.

Now we can run the application using dab start which will start the Data ApiBuilder server on http://localhost:5000 endpoint. If we browse the endpoint, which will return a JSON response like this.

{
  "status": "Healthy",
  "version": "1.6.84",
  "app-name": "dab_oss_1.6.84"
}

Next we can browse /swagger endpoint which will return Open API documentation with all the table CRUD operations. Here is an screenshot of the application running on my machine.

We can access GraphQL endpoint using the /graphql. Here is the screenshot of the GraphQL endpoint running on my machine.

We can deploy it using Data ApiBuilder docker image. Here is the command.

docker run \
    --name dab \
    --publish 5000:5000 \
    --detach \
    --mount type=bind,source=$(pwd)/dab-config.json,target=/App/dab-config.json,readonly \
    mcr.microsoft.com/azure-databases/data-api-builder

We may have to modify the connection string in the dab-config.json file, since we are running the SQL Server in Docker, like this.

We need to modify the connection string - servername to host.docker.internal instead of localhost. This way we can expose the database and tables using Data ApiBuilder and how we can deploy the Data ApiBuilder in docker.

Happy Programming.