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 bho_sud_continuity_of_care_20102014 table in this repository, by referencing it like:
"ny-gov/bho-sud-continuity-of-care-20102014-58ew-qhce:latest"."bho_sud_continuity_of_care_20102014"or in a full query, like:
SELECT
":id", -- Socrata column ID
"metric_id", -- Numeric Code that uniquely identifies the Metric
"row_created_date_time", -- Date and Time when data was generated (e.g. “12/19/2014 09:45:21”)
"age_group", -- Standardized Age Groups; either “Adult” or “Children”. All SUD metrics are reported for the “Adult” Age Group (defined as age 18 and up)
"denominator", -- The denominator includes discharges from chemical dependence inpatient rehabilitation identified from paid fee-for-service Medicaid claims. Individuals who meet any of the following criteria are excluded: Ineligible for Medicaid in any of the 30 days post discharge; Medicare-eligible.
"description_of_metric", -- Short description of the BHO Performance Metric. For this SUD Continuity of Care dataset, there are eight possible metrics: 1. Percentage of SUD Detox Discharges Followed by a Lower Level SUD Service within 14 Days; 2. Percentage of SUD Rehabilitation Discharges Followed by a Lower Level SUD Service within 14 Days; 3. Percentage of SUD Detox Discharges Followed by a Lower Level SUD Service or MH Outpatient Treatment within 14 Days; 4. Percentage of SUD Rehabilitation Discharges Followed by a Lower Level SUD Service or MH Outpatient Treatment within 14 Days; 5. Percentage of SUD Detox Discharges Followed by a Lower Level SUD Service within 30 Days; 6. Percentage of SUD Rehabilitation Discharges Followed by a Lower Level SUD Service within 30 Days; 7. Percentage of SUD Detox Discharges Followed by a Lower Level SUD Service or MH Outpatient Treatment within 30 Days; 8. Percentage of SUD Rehabilitation Discharges Followed by a Lower Level SUD Service or MH Outpatient Treatment within 30 Days. More detailed descriptions of these metrics are provided in the “Detailed Metric Definitions” table in the data dictionary attached to this dataset.
"year_to_date_rate", -- For the Performance Metric and the Quarter being examined, this is the rate of the metric as calculated by dividing the Year to Date Numerator by the Year to Date Denominator.
"year", -- 4 Digit year for which the metric is calculated
"rate", -- For the Age Group, OMH Region, Performance Metric and Quarter being examined, this is the rate of the metric as calculated by dividing the Numerator by the Denominator.
"indicator_domain_group", -- This is the domain group that the BHO Performance Indicator belongs to. For this dataset, the domain group is “SUD Continuity of Care”
"year_to_date_denominator", -- Value of the bottom of the "Rate" calculation for the Age Group, OMH Region, Performance Metric and Year to Date being examined. For example, for the metric "14 Day SUD Detox (SUD Follow-Up)" in Q4 of 2012, this is the number of all patients discharged from chemical dependence inpatient rehabilitation identified from paid fee-for-service Medicaid claims during Quarters 1,2, 3 and 4 of that year.
"year_to_date_numerator", -- Value of the "top" of the "Rate" calculation for the year to date as of the Quarter that is being examined. For example, for the metric "14 Day SUD Detox (SUD Follow-Up)" in Q4 of 2012, the Numerator is the number of discharges in the denominator where the individual had a substance use disorder non-crisis treatment service within 14 days post discharge from inpatient detoxification during Quarters 1, 2, 3 and 4 of 2012.
"quarter", -- Quarter for which the metric is calculated: Q1, Q2, Q3, Q4 or some combination of one or two quarters (beginning in 2013, data is collected semi-annually)
"numerator", -- Value of the "top" of the "Rate" calculation for the Age Group, OMH Region, Performance Metric and Quarter that is being examined. The description of the Numerator is specific to the metric being evaluated. For more detail on the numerator for each metric, see the “Detailed Metric Descriptions” table in the data dictionary attached to this dataset.
"omh_region" -- Name of the OMH Region for which the Indicator is calculated
FROM
"ny-gov/bho-sud-continuity-of-care-20102014-58ew-qhce:latest"."bho_sud_continuity_of_care_20102014"
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 ny-gov/bho-sud-continuity-of-care-20102014-58ew-qhce with SQL in under 60 seconds.
This repository is an "external" repository. That means it's hosted elsewhere, in this case at data.ny.gov. When you queryny-gov/bho-sud-continuity-of-care-20102014-58ew-qhce: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)"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 (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.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 \
"ny-gov/bho-sud-continuity-of-care-20102014-58ew-qhce" \
--handler-options '{
"domain": "data.ny.gov",
"tables": {
"bho_sud_continuity_of_care_20102014": "58ew-qhce"
}
}'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, ny-gov/bho-sud-continuity-of-care-20102014-58ew-qhce is just another Postgres schema.