Query the Data Delivery Network

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 protocol. Any Splitgraph user can connect to it at data.splitgraph.com:5432 and query any version of over 40,000 datasets that are hosted or proxied by Splitgraph.

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

"health-data-ny-gov/child-and-adult-care-food-program-participation-dmn7-mpa8:latest"."child_and_adult_care_food_program_participation"

or in a full query, like:

SELECT
    ":id", -- Socrata column ID
    "site_name", -- Name of the participating site
    "county", -- Counties where the participating site is located
    "zipcode_zip",
    "breastfeeding_friendly_certified", -- The Child and Adult Care Food Program encourages child care centers and family day care homes to support breastfeeding families and recognizes these providers with Breastfeeding Friendly certificates. Participating sites that have completed the requirements to obtain a certificate are designated as Breastfeeding Friendly. Values are Yes and No.
    "approval_license_type", -- Approval /License Type of the participating site
    "address_omitted", -- A “Y” value indicates the address is not included in the dataset. Addresses have been omitted for regulated child care providers that provide home care since this information is available on Open.ny.gov by using this link: https://data.ny.gov/Human-Services/Child-Care-Regulated-Programs/cb42-qumz
    "eat_well_play_hard_ccs_participant", -- Day Care Center sites that have completed the full Eat Well Play Hard in Child Care Settings (EWPHCCS) educational program of child, parent and staff classes. Values are Yes and No.
    "city", -- City of the participating site
    "street1", -- Street Address1 of the participating site
    "eat_well_play_hard_dch_participant", -- Day Care Home Provider Sites that have completed the full Eat Well Play Hard in Day Care Homes (EWPHDCH) environmental program requirements. In particular, DCH providers are asked to focus on increasing the variety of fruits and vegetables offered at the DCH and increasing opportunities for adult-led structured play. Values are Yes and No.
    "location_state",
    "zipcode_state",
    "program_type", -- Program Type of the participating site (Home or Center)
    "last_ewphccs_participation", -- The most recent year a center has participated in the Eat Well Play Hard in Child Care Settings program
    "street2", -- Street Address2 of the participating site
    "zipcode_address",
    "last_ewphdch_participation", -- The most recent year a center has participated in the EWPHDCH program
    "location", -- Location
    "location_address",
    "location_city",
    "zipcode_city",
    "location_zip",
    "state", -- State the participating site is located
    "zipcode", -- Zip code of the participating site
    "site_type" -- Site types are: Adult Care, Child Care, Head Start, Licensed, Military, Registered, School Age, and Tribal
FROM
    "health-data-ny-gov/child-and-adult-care-food-program-participation-dmn7-mpa8:latest"."child_and_adult_care_food_program_participation"
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 health-data-ny-gov/child-and-adult-care-food-program-participation-dmn7-mpa8 with SQL in under 60 seconds.

This repository is an "external" repository. That means it's hosted elsewhere, in this case at health.data.ny.gov. When you queryhealth-data-ny-gov/child-and-adult-care-food-program-participation-dmn7-mpa8: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

bash -c "$(curl -sL https://github.com/splitgraph/splitgraph/releases/latest/download/install.sh)"

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 health.data.ny.gov, 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 \
  "health-data-ny-gov/child-and-adult-care-food-program-participation-dmn7-mpa8" \
  --handler-options '{
    "domain": "health.data.ny.gov",
    "tables": {
        "child_and_adult_care_food_program_participation": "dmn7-mpa8"
    }
}'

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, health-data-ny-gov/child-and-adult-care-food-program-participation-dmn7-mpa8 is just another Postgres schema.