Query the Data Delivery NetworkQuery 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 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
covid19_vaccinations_by_gender_current_statewide table in this repository, by referencing it like:
or in a full query, like:
":id", -- Socrata column ID
"additional_dose", -- First Booster doses administered since August 13, 2021 includes vaccinations beyond the primary series administered to the suggested groups at the recommended intervals on or after 08-13-2021 following CDC guidelines. Such vaccinations are commonly called booster doses. This category also includes additional does of COVID vaccine administered on or after 08-13-2021 to immunocompromised individual at the CDC recommended interval.
"gender", -- Gender of the individuals receiving vaccinations. Male, Female and Unknown
"bivalent_booster_1", -- Bivalent booster doses include vaccinations using the bivalent formulation of Moderna and Pfizer vaccines beyond the primary series administered to the recommended age groups on or after September 2, 2022 following CDC guidelines. The updated (bivalent) boosters are called “bivalent” because they protect against both the original virus that causes COVID-19 and the Omicron variant BA.4 and BA.5. Bivalent Booster doses for children under 12 years old are not authorized at this time.
"additional_dose_2", -- Second booster doses administered since March 29, 2022 includes mRNA vaccinations beyond the primary series and one additional COVIDS vaccine as a second booster dose administered on or after 03-29-2022 to individuals ages 50+ at the recommended intervals per CDC guidelines. This category also includes additional doses of mRNA COVID vaccines administered on or after 03-29-2022 to immunocompromised individual at the CDC recommended internal.
"partially_covered", -- Quantity of individuals who have received a vaccine that provides partial coverage against COVID disease. For 2-shot vaccine 1-shot is partial. For the J&J 1-shot vaccine this will be counted in the full coverage. This is the total current count.
"fully_covered" -- Quantity of individuals who have received a vaccine that provides full coverage against COVID disease. For 2-shot vaccine 1-shot is partial. For the J&J 1-shot vaccine this will be counted in the full coverage. This is the total current count.
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
pa-gov/covid19-vaccinations-by-gender-current-statewide-id8t-dnk6 with SQL in under 60 seconds.
This repository is an "external" repository. That means it's hosted elsewhere, in this case at data.pa.gov. When you query
pa-gov/covid19-vaccinations-by-gender-current-statewide-id8t-dnk6: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
This repository is an external repository. It's not hosted by Splitgraph. It is hosted by data.pa.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 socrata \
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,
pa-gov/covid19-vaccinations-by-gender-current-statewide-id8t-dnk6 is just another Postgres schema.