PostgreSQL Support in the Data API Builder

Next week I’m at VS Live in San Diego (register and join me) and one of my talks is on the Data API Builder. I want to show how this gives you REST, GRAPHQL, and MCP access. As a part of the talk, I also wanted to show this working across platforms, so I’m showing this in PostgreSQL as well.

I’ve been experimenting this in a few ways, but I decided to see how hard it was to add PostgreSQL support. I decided to follow a similar structure as my SQL Server demos, which are all in my GitHub repo.

First, I added a .env file, which has the credentials. THIS IS A DEVELOPMENT structure, and not something you’d deploy from a repo. Secure your production stuff! This is my local file (in .gitignore), but it’s a simple connection string.

Next, I copied (well, I guided Claude to do this)  my demo01.cmd and edited it to say the type is “postgresql” instead of SQL Server. The new file went into a separate folder as (demo01.cmd)

I had it copy the demo02.cmd and alter this for the PostgreSQL Pagila sample db, which is installed and running on my machine.

Note, this errored out at first, with the note that DAB doesn’t support the PostgreSQL array type. I ended up having Claude create a view that skips this column and the column that is a vector type. Hopefully those will be supported soon by DAB.

Next, dab start, and I had a running API server over my PostgreSQL database in just a few minutes. Here’s my Bruno query of the GraphQL endpoint for Pagila.

Not enough people are using or trying the Data API Builder. This is truly an easy way to get a usable API over your database without a lot of data access layer work for developers.