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 officer_involved_shootings table in this repository, by referencing it like:
"policedata-coloradosprings-gov/officer-involved-shootings-pzyt-rvyq:latest"."officer_involved_shootings"or in a full query, like:
SELECT
":id", -- Socrata column ID
"subject_designator", -- Number assigned to each subject in an officer involved shooting to make it easier for consumers of the data to know whether there is more than one subject in a particular incident.
"weapon_subject_was_armed", -- Weapon subject was armed with at the time of the shooting. Options are determined by the State of Colorado.
"subject_armed", -- Whether the subject was armed with a weapon
"subject_physical_or_mental", -- Physical or mental disability of the person shot/shot at . Options are determined by the State of Colorado.
"subject_sexual_orientation", -- Sexual orientation of the person shot/shot at. Options are determined by the State of Colorado.
"primary_basis_for_shooting", -- Reason officer(s) shot/shot at the subject. Options are determined by the State of Colorado.
"officer_race",
"officer_age",
"contraband_type", -- If a search was conducted by an officer prior to the shooting, and contraband was found, the type of contraband found. Options are determined by the State of Colorado.
"prior_to_shooting_officer", -- Whether or not an officer conducted a search prior to the shooting
"subject_arrested_or_cited", -- Whether the subject of the shooting was arrested or cited for a crime. Options are determined by the State of Colorado.
"subject_ethnicity", -- Whether the person has Hispanic ethnicity. Options are determined by the State of Colorado.
"subject_race", -- Race of the person shot/shot at. Options are determined by the State of Colorado.
"subject_was_charged_with", -- The Colorado Revised Statute corresponding to the most serious charge
"subject_wounded_or_killed", -- Whether the subject of the shooting sustained any injuries or was killed. Options are determined by the State of Colorado.
"subject_gender", -- Gender of the person shot/shot at. Options are determined by the State of Colorado.
"subject_under_the_influence", -- Whether the subject of the shooting was under the influence of drugs and/or alcohol. Options are determined by the State of Colorado.
"officer_issued_verbal_warning", -- Indicates whether or not the officer was able to give a verbal warning before shooting their firearm.
"officer_ethnicity",
"type_of_search_conducted", -- The type of search that was conducted by an officer prior to the shooting. Options are determined by the State of Colorado.
"officer_gender",
"officer_wounded_or_killed", -- Whether the officer(s) in the shooting sustained any injuries or was killed. Options are determined by the State of Colorado.
"incident_narrative", -- Short incident narrative
"subject_age", -- Age of the person shot/shot at
"primary_basis_for_initial", -- Reason officers initially contacted the subject of the shooting. Options are determined by the State of Colorado.
"incident_location", -- Location of shooting
"incident_date", -- Date and time shooting occurred
"cspd_case_number_agency", -- Case number (may be CSPD's or the investigative agencies' number)
"incident_count", -- The number CSPD uses to count the number of officer involved shootings in the dataset. Each incident may have multiple involved officers or subjects.
"contraband_found" -- If a search was conducted by an officer prior to the shooting, whether contraband was found in the search.
FROM
"policedata-coloradosprings-gov/officer-involved-shootings-pzyt-rvyq:latest"."officer_involved_shootings"
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 policedata-coloradosprings-gov/officer-involved-shootings-pzyt-rvyq 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 policedata-coloradosprings-gov/officer-involved-shootings-pzyt-rvyq: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 policedata-coloradosprings-gov/officer-involved-shootings-pzyt-rvyqCheckout 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 policedata-coloradosprings-gov/officer-involved-shootings-pzyt-rvyq:latestThis will download all the objects for the latest tag of policedata-coloradosprings-gov/officer-involved-shootings-pzyt-rvyq 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 policedata-coloradosprings-gov/officer-involved-shootings-pzyt-rvyq: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 policedata-coloradosprings-gov/officer-involved-shootings-pzyt-rvyq: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, policedata-coloradosprings-gov/officer-involved-shootings-pzyt-rvyq is just another Postgres schema.