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 iowa_pandemic_recovery_reporting_federal_funds table in this repository, by referencing it like:
"mydata-iowa-gov/iowa-pandemic-recovery-reporting-federal-funds-a5qe-4idi:latest"."iowa_pandemic_recovery_reporting_federal_funds"or in a full query, like:
SELECT
":id", -- Socrata column ID
"record_id", -- Unique identifier for the record; concatenation of federal_award_number and, if applicable, award_amend with a dash (“-”) in between.
"federal_award_number", -- The unique identifier of the specific award being reported. Federal Award Identification Number (FAIN) for federal assistance or the Procurement Instrument Identifier (PIID) for procurement.
"award_amend", -- The Federal identifier for subsequent change or supplement to the initial award, assigned by awarding federal agency.
"federal_program", -- The number assigned to the federal assistance listing (formerly known as CFDA)
"federal_department", -- The name of the federal department responsible for the federal award.
"federal_agency", -- The name of the office, administration or service within the federal department responsible for the award. If not specifically defined, same as the federal department.
"federal_program_title", -- Name of the federal program through which the award was made.
"state_dept_no", -- The three digit code used in the State Accounting System for the department who is the prime recipient of the award
"state_department", -- Name of the State department awarded the federal funds.
"duns_number", -- The unique 9-digit number assigned by Dun and Bradstreet (D&B) referred to as the DUNS® used in the Federal System for Award Management for the state agency on the award received.
"award_date", -- The date of the initial federal award or subsequent amendment
"award_description", -- A brief description of the purpose of the award.
"performance_start", -- The date on which effort begins or the award is otherwise effective, or, if applicable, when the emergency declaration began
"performance_end", -- The date on which effort related to the award ends or is completed, or, if applicable, when the emergency declaration ended.
"award_amount", -- The total amount of the initial award or subsequent amendment, or, if applicable, the estimate associated with federal match increase during emergency declaration.
"fiscal_year" -- The state fiscal year the federal funds were awarded.
FROM
"mydata-iowa-gov/iowa-pandemic-recovery-reporting-federal-funds-a5qe-4idi:latest"."iowa_pandemic_recovery_reporting_federal_funds"
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 mydata-iowa-gov/iowa-pandemic-recovery-reporting-federal-funds-a5qe-4idi 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 mydata-iowa-gov/iowa-pandemic-recovery-reporting-federal-funds-a5qe-4idi: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 mydata-iowa-gov/iowa-pandemic-recovery-reporting-federal-funds-a5qe-4idiCheckout 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 mydata-iowa-gov/iowa-pandemic-recovery-reporting-federal-funds-a5qe-4idi:latestThis will download all the objects for the latest tag of mydata-iowa-gov/iowa-pandemic-recovery-reporting-federal-funds-a5qe-4idi 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 mydata-iowa-gov/iowa-pandemic-recovery-reporting-federal-funds-a5qe-4idi: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 mydata-iowa-gov/iowa-pandemic-recovery-reporting-federal-funds-a5qe-4idi: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, mydata-iowa-gov/iowa-pandemic-recovery-reporting-federal-funds-a5qe-4idi is just another Postgres schema.