Query the Data Delivery Network
Query the DDNThe 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 quality_assurance_reporting_requirements_qarr table in this repository, by referencing it like:
"health-data-ny-gov/quality-assurance-reporting-requirements-qarr-brzd-i7d8:latest"."quality_assurance_reporting_requirements_qarr"or in a full query, like:
SELECT
":id", -- Socrata column ID
"domain", -- The measures in QARR are divided into seven domains: Provider, Network, Access to Primary Care, Child and Adolescent Health, Women’s Health, Adult Health, Behavioral Health, and Satisfaction with Care. Information from the Consumer Assessment of Healthcare Providers and Systems (CAHPS) consumer satisfaction survey is included in the Provider Network, Adults Living with Illness, as well as in the Satisfaction with Care sections.
"category", -- This field reflects characteristics that are extracted from the member information that is collected during enrollment and is linked to QARR member-level data. The categories of demographic information include: members’ gender, age, race/ethnicity, Medicaid aid category, payer status, cash assistance status, mental health condition, substance use, and region of residence.
"method_of_data_collection", -- Methods of collecting quality data are administrative review, hybrid review, and the CAHPS survey. Administrative review utilizes administrative systems only to identify the eligible population, numerator events, and exclusions to calculate a rate. Hybrid review utilizes administrative systems to use a sample of the eligible population in addition to medical chart review. The CAHPS survey is an annual survey that asks consumers and patients to report on and evaluate their experiences with health care.
"measure", -- Measure short name that corresponds to the short name in the QARR dataset file.
"measure_description", -- Description of quality measure. This dataset contains 66 measures from the QARR.
"payer", -- Medicaid Managed Care, Commercial HMO, Commercial PPO.
"denominator", -- Number of persons meeting denominator criteria specified by HEDIS 2019 within each characteristic.
"rate", -- Percentage of numerator compliant within the denominator criteria.
"numerator", -- Number of persons within each characteristic.
"characteristics", -- This field reflects the range of values that are appropriate for each demographic category.
"sub_domain", -- Category within the domain with more detailed information regarding a certain aspect of quality.
"measurement_year" -- The time period the data represent.
FROM
"health-data-ny-gov/quality-assurance-reporting-requirements-qarr-brzd-i7d8:latest"."quality_assurance_reporting_requirements_qarr"
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/quality-assurance-reporting-requirements-qarr-brzd-i7d8 with SQL in under 60 seconds.
Query Your Local Engine
bash -c "$(curl -sL https://github.com/splitgraph/splitgraph/releases/latest/download/install.sh)"Read the installation docs.
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, 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 (like this repository), where the author has pushed Splitgraph Images to the repository, you can "clone" and/or "checkout" the data using sgr cloneand sgr checkout.
Cloning Data
Because health-data-ny-gov/quality-assurance-reporting-requirements-qarr-brzd-i7d8:latest is a Splitgraph Image, you can clone the data from Spltgraph Cloud to your local engine, where you can query it like any other Postgres database, using any of your existing tools.
First, install Splitgraph if you haven't already.
Clone the metadata with sgr clone
This will be quick, and does not download the actual data.
sgr clone health-data-ny-gov/quality-assurance-reporting-requirements-qarr-brzd-i7d8Checkout the data
Once you've cloned the data, you need to "checkout" the tag that you want. For example, to checkout the latest tag:
sgr checkout health-data-ny-gov/quality-assurance-reporting-requirements-qarr-brzd-i7d8:latestThis will download all the objects for the latest tag of health-data-ny-gov/quality-assurance-reporting-requirements-qarr-brzd-i7d8 and load them into the Splitgraph Engine. Depending on your connection speed and the size of the data, you will need to wait for the checkout to complete. Once it's complete, you will be able to query the data like you would any other Postgres database.
Alternatively, use "layered checkout" to avoid downloading all the data
The data in health-data-ny-gov/quality-assurance-reporting-requirements-qarr-brzd-i7d8:latest is 0 bytes. If this is too big to download all at once, or perhaps you only need to query a subset of it, you can use a layered checkout.:
sgr checkout --layered health-data-ny-gov/quality-assurance-reporting-requirements-qarr-brzd-i7d8:latestThis will not download all the data, but it will create a schema comprised of foreign tables, that you can query as you would any other data. Splitgraph will lazily download the required objects as you query the data. In some cases, this might be faster or more efficient than a regular checkout.
Read the layered querying documentation to learn about when and why you might want to use layered queries.
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/quality-assurance-reporting-requirements-qarr-brzd-i7d8 is just another Postgres schema.