Voice of the DBA

Tag: DAB

Using the Data API Builder–VS Live San Diego Resources

Thanks for attending my sessions. Resources below:

Slides: Using Data API Builder

GitHub repo: https://github.com/way0utwest/DAB-Experiments

September 16, 2026
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.

September 9, 2026
Updating the Data API Builder
I was updating my session for the Data API Builder (DAB) recently, mostly to work with the MCP server capabilities. As I was trying to get this working, I realized that the MCP capabilities were newer than my DAB version. I had v1.4

Wow, that’s old. The Overview page for the SQL Server MCP site says v1.7 is needed and 2.0+ has bug fixes. I need an update.

I had this in my slide deck, but the dotnet tool is used to update the DAB. The command is
```
dotnet tool update –-global Microsoft.DataApiBuilder
```
This showed a download and then in a few minutes it was done. I could see I had an updated version.

And an MCP server!

A Further Update

I checked a few weeks later and couldn’t remember the command, but I decided to try the install command. That worked as well, and I got an even newer, 2.0.12, version.

Still no timestamps from the logs, but I’m every hopeful.
September 2, 2026
Accessing the Data API Builder MCP Server from VS Code
I recently started playing with the MCP Server for SQL Server, which is a part of the Data API Builder (DAB). I’m not sure why there wasn’t a separate piece of technology used, but I do think the DAB server is very useful, and I wish more people used it. Adding MCP to it makes some sense, as the REST and GRAPHQL endpoints can be disabled.

This post will look at a few things I did to get the MCP server working.

A Default for New Projects

By default, if you have v2.xx of the Data API Builder, when you create a new project (with dab init), you get this section in your json config file with the mcp entry.:
```
"mcp": {
   "enabled": true,
   "path": "/mcp"
}
```
This is the enabling of the MCP server. In my files, this was added below the “rest” and “graphql” sections under the “runtime” key. You can see this in a larger view of the file.

Once you add this, the MCP server should start up with DAB. The only indication I see in the logs is this message that the endpoints are enabled.

Adding an MCP Server to VS Code

My first experiment here was adding a server to VS Code. This isn’t a clear thing in the docs, to me, so I’ll tell you what worked for me. I already have some MCP servers in VS Code, so I really went through this process.

First, this is an http MCP server, and the URL is the DAB URL (for me: http://localhost:5000/mcp) that I’ll use to connect. I used the instructions in this VS Code article rather than the quickstart in the DAB docs.

In the VSCode command palette, I looked for the “MCP: Add Server” entry, as shown.

I then picked the http option:

Next, I enter the UL. I’ve pasted mine in here.

Give this a name. This isn’t clear in docs, but this is the name that you’ll use when starting this MCP server. I chose dab-northwind-mcp, which lets me know this corresponds to my config file and it’s a dab server.

Next we decide where this is available. I usually choose workspace, but the setting depends on what you doing with this server. I tend to aim to keep things more tightly configured, so that if I need it elsewhere, I can learn how to adjust that, or add this as an item for another workspace.

I then get my mcp.json file, which is the config file for the MCP servers in VS Code. These servers are a part of the “servers” key, as an sub-document below that. Each of these is a separate entry in JSOn. I essentially have two of the same here, the sql-northwind and dab-northwind-mcp point to the same server.

Starting the MCP Server

If you look at the image above, there’s a “start” link that VS Code adds as an annotation to the entry. You can click that. For me, I usually go back to the command palette and get to the “MCP: List Servers” entry.

Then I see a list of servers and I’ll select the one I want. In this case, that’s the dab-northwind-mcp one.

I see a few items. The configuration will open the mcp.json. It brings up output by default. I’ll pick “Start Server”

I can see in the output it starts. notice I have some errors, this is because the DAB server wasn’t running. I started it, and then went through the process above to get it restarted. You can see tools were discovered.

That’s it. The MCP server is active and running. I’ll do another post on how I can use this.
August 19, 2026