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 covid19_vaccination_demographics_in_the_united table in this repository, by referencing it like:
"cdc-gov/covid19-vaccination-demographics-in-the-united-km4m-vcsb:latest"."covid19_vaccination_demographics_in_the_united"or in a full query, like:
SELECT
":id", -- Socrata column ID
"bivalent_booster_pop_pct_known", -- Percent of people with a bivalent booster dose who have known demographic information for the selected demographic category
"second_booster_pop_pct_us", -- Percent of population aged 50 years and older with a completed primary series and a first booster dose who have known demographic information for the selected demographic category
"second_booster_pop_pct_known", -- Percent of people aged 50 years and older with a first booster who have received a second booster dose and have known demographic information for the selected demographic category
"booster_doses_yes_last14days", -- People 12+ with a booster dose in the last 14 days
"booster_doses_yes", -- People 12+ with a booster dose
"booster_doses_pop_pct_known_last14days", -- Percent of population aged 5 years and older with a completed primary series and a booster dose (within the last 14 days) who have known demographic information for the selected demographic category
"booster_doses_pop_pct_known", -- Percent of people aged 5 years and older with a completed primary series who received a booster dose and have known demographic information for the selected demographic category
"administered_dose1_pct", -- Percent among persons with at least one dose in demographic category
"series_complete_yes", -- Total count of people who completed a primary series
"administered_dose1", -- Total count of people with at least one dose in demographic category
"demographic_category", -- Age, sex or race/ethnicity of person receiving vaccination
"date", -- Date data are reported on CDC COVID Data Tracker
"bivalent_booster", -- Total count of people aged 5 years and older with a bivalent booster dose
"second_booster_pop_pct_known_last14days", -- Percent of people aged 50 years and older with a first booster who have received a second booster dose (within the last 14 days) and have known demographic information for the selected demographic category
"series_complete_pop_pct_us", -- Percent of people with a completed primary series who have known demographic information for the selected demographic category
"bivalent_booster_pop_pct_agegroup", -- Percent of people in a demographic category who have a bivalent booster dose who have information for the selected demographic category
"booster_doses_vax_pct_us", -- Percent of the fully vaccinated population aged 5 years and older with a completed primary series and a booster dose who have known demographic information for the selected demographic category
"administered_dose1_pct_known", -- Percent among persons with at least one dose who are Hispanic/Latino
"booster_doses_vax_pct_agegroup", -- Percent of people aged 5 years and older with a completed primary series in a demographic category who have received a booster dose and have information for the selected demographic category
"series_complete_pop_pct_known", -- Percent of people with a completed primary series who have known demographic information for the selected demographic category
"second_booster_last14days", -- Total count of people aged 50 years and older with a second booster dose in the last 14 days
"second_booster", -- Total count of people aged 50 years and older with a second booster dose
"second_booster_vax_pct_agegroup", -- Percent of people aged 50 years and older in a demographic category with a first booster dose who have received a second booster dose and have information for the selected demographic category
"series_complete_pop_pct", -- Percent of people in a demographic category who have completed a primary series and have information for the selected demographic category
"administered_dose1_pct_us" -- Percent among persons with at least one dose, who have demographic information available on age, race/ethnicity or sex
FROM
"cdc-gov/covid19-vaccination-demographics-in-the-united-km4m-vcsb:latest"."covid19_vaccination_demographics_in_the_united"
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 cdc-gov/covid19-vaccination-demographics-in-the-united-km4m-vcsb 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 cdc-gov/covid19-vaccination-demographics-in-the-united-km4m-vcsb: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 cdc-gov/covid19-vaccination-demographics-in-the-united-km4m-vcsbCheckout 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 cdc-gov/covid19-vaccination-demographics-in-the-united-km4m-vcsb:latestThis will download all the objects for the latest tag of cdc-gov/covid19-vaccination-demographics-in-the-united-km4m-vcsb 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 cdc-gov/covid19-vaccination-demographics-in-the-united-km4m-vcsb: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 cdc-gov/covid19-vaccination-demographics-in-the-united-km4m-vcsb: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, cdc-gov/covid19-vaccination-demographics-in-the-united-km4m-vcsb is just another Postgres schema.