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 licensed_child_care_providers_and_facilities table in this repository, by referencing it like:

"delaware-gov/licensed-child-care-providers-and-facilities-iuzd-3dbt:latest"."licensed_child_care_providers_and_facilities"

or in a full query, like:

SELECT
    ":id", -- Socrata column ID
    "site_closes_at", -- The closing time of the child care.  This is presented as a 24 hour clock (for example, 17:00 = 5:00PM).
    "special_conditions", -- Special Conditions for this child care, such as:  High Nitrate Water, Foster Care.
    "site_zip_code", -- The zip code of the child care.
    "enforcement_action", -- Current enforcement status.  If blank, there is no current enforcement action.
    "site_state", -- The state of the child care. 
    "age_group", -- Age group of children served by this child care facility. Examples are "Infant through Pre-School" and "School-Age" .
    "resource_type", -- Type of child care:  Family Child Care, Large Family Child Care, and Child Care Center.
    "intent_to_revoke", -- The Office of Child Care Licensing has begun the process to revoke the license of the child care provider.
    "site_street_address", -- Street address of the child care.
    "count", -- This is used strictly for providing counts and summaries of the data and is otherwise not relevant to this specific row in this dataset. The value will always be "1".
    "age_range", -- Ages of children served by this child care.
    "geocoded_location",
    "site_county", -- The county where the child care is located.
    "injuries_report", -- Reported injuries over the last 5 years that involved medical or dental treatment
    "resource_name_reversed", -- Last name, first name when it is an individual provider.
    "site_city", -- The city of the child care.
    "site_opens_at", -- The opening time of the child care.
    "financial_arrangements", -- Government programs that the child care provider participates in.  Child Care Food Program = the child care provider is reimbursed a certain amount for each meal provided. Purchase of Care = State subsidized child care.
    "resource_id", -- The license number issued by the State of Delaware.
    "phone_number", -- The phone number of the child care.
    "resource_name", -- The name of the child care provider or facility.
    "capacity" -- The maximum number of children that can be served by this child care at one time.
FROM
    "delaware-gov/licensed-child-care-providers-and-facilities-iuzd-3dbt:latest"."licensed_child_care_providers_and_facilities"
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/licensed-child-care-providers-and-facilities-iuzd-3dbt with SQL in under 60 seconds.

This repository is an "external" repository. That means it's hosted elsewhere, in this case at data.delaware.gov. When you querydelaware-gov/licensed-child-care-providers-and-facilities-iuzd-3dbt: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 data.delaware.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 \
  "delaware-gov/licensed-child-care-providers-and-facilities-iuzd-3dbt" \
  --handler-options '{
    "domain": "data.delaware.gov",
    "tables": {
        "licensed_child_care_providers_and_facilities": "iuzd-3dbt"
    }
}'

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/licensed-child-care-providers-and-facilities-iuzd-3dbt is just another Postgres schema.