Icon for Socrata external plugin

Query the Data Delivery Network

Query the DDN

The easiest way to query any data on Splitgraph is via the "Data Delivery Network" (DDN). The DDN is a single endpoint that speaks the PostgreSQL wire procotol. Any Splitgraph user can connect to it at and query any version of over 40,000 datasets that are hosted or proxied by Splitgraph.

For example, you can query the electric_vehicle_charging_equipment_rebates table in this repository, by referencing it like:


or in a full query, like:

    ":id", -- Socrata column ID
    "charging_station_brand", -- Company brand of charging station equipment
    "zip", -- Zip code of charging station location
    "award_number", -- Unique identifier for each grant application. Alpha-numeric. Begins with letters signifying the type of rebate award (EVSE = electronic vehicle supply equipment, RCS = residential charging station, CCS = commercial charging station, or WCS = workplace charging station). Ends with 6 digits signifying the date of the application (MMYY) and the numerical order in which applications were received by the state.
    "year", -- Year of application submission
    "county", -- County of charging station location
    "cost_of_charging_station", -- Total dollars spent on charging station equipment
    "month", -- Month of application submission
    "city", -- City of charging station location
    "rebate_amount" -- Total dollars awarded to applicant for charging station equipment. Residential equipment purchased prior to November 1, 2016 received 100% of the cost of the charging station, up to $500; residential equipment purchased after November 1, 2016 received 50% of the cost of the charging station, up to $500. Commercial equipment receives 75% of the cost of the charging station, up to $2500. Workplace equipment receives 75% of the cost of the charging station, up to $5000.
LIMIT 100;

Connecting to the DDN is easy. All you need is an existing SQL client that can connect to Postgres. As long as you have a SQL client ready, you'll be able to query delaware-gov/electric-vehicle-charging-equipment-rebates-a9zd-p6sk with SQL in under 60 seconds.

This repository is an "external" repository. That means it's hosted elsewhere, in this case at When you querydelaware-gov/electric-vehicle-charging-equipment-rebates-a9zd-p6sk:latest on the DDN, we "mount" the repository using the socrata mount handler. The mount handler proxies your SQL query to the upstream data source, translating it from SQL to the relevant language (in this case SoQL).

We also cache query responses on the DDN, but we run the DDN on multiple nodes so a CACHE_HIT is only guaranteed for subsequent queries that land on the same node.

Query Your Local Engine

Install Splitgraph Locally
bash -c "$(curl -sL"

Splitgraph Cloud is built around Splitgraph Core (GitHub), which includes a local Splitgraph Engine packaged as a Docker image. Splitgraph Cloud is basically a scaled-up version of that local Engine. When you query the Data Delivery Network or the REST API, we mount the relevant datasets in an Engine on our servers and execute your query on it.

It's possible to run this engine locally. You'll need a Mac, Windows or Linux system to install sgr, and a Docker installation to run the engine. You don't need to know how to actually use Docker; sgrcan manage the image, container and volume for you.

There are a few ways to ingest data into the local engine.

For external repositories (like this repository), the Splitgraph Engine can "mount" upstream data sources by using sgr mount. This feature is built around Postgres Foreign Data Wrappers (FDW). You can write custom "mount handlers" for any upstream data source. For an example, we blogged about making a custom mount handler for HackerNews stories.

For hosted datasets, where the author has pushed Splitgraph Images to the repository, you can "clone" and/or "checkout" the data using sgr cloneand sgr checkout.

Mounting Data

This repository is an external repository. It's not hosted by Splitgraph. It is hosted by, and Splitgraph indexes it. This means it is not an actual Splitgraph image, so you cannot use sgr clone to get the data. Instead, you can use the socrata adapter with the sgr mount command. Then, if you want, you can import the data and turn it into a Splitgraph image that others can clone.

First, install Splitgraph if you haven't already.

Mount the table with sgr mount

sgr mount socrata \
  "delaware-gov/electric-vehicle-charging-equipment-rebates-a9zd-p6sk" \
  --handler-options '{
    "domain": "",
    "tables": {
        "electric_vehicle_charging_equipment_rebates": "a9zd-p6sk"

That's it! Now you can query the data in the mounted table like any other Postgres table.

Query the data with your existing tools

Once you've loaded the data into your local Splitgraph engine, you can query it with any of your existing tools. As far as they're concerned, delaware-gov/electric-vehicle-charging-equipment-rebates-a9zd-p6sk is just another Postgres schema.

Related Documentation: