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 governors_executive_budget_program_measures_sfy table in this repository, by referencing it like:
"pa-gov/governors-executive-budget-program-measures-sfy-d2fn-fwqd:latest"."governors_executive_budget_program_measures_sfy"or in a full query, like:
SELECT
":id", -- Socrata column ID
"public_hearings_held_to", -- This measure represents the number of public hearings held to consider the level and duration of the Class 1 over-order premium. The over-order premium is an amount that is paid to Pennsylvania producers over the applicable Federal Order price for Class 1 (beverage) milk produced, processed, and sold in Pennsylvania.
"audits_of_milk_dealers_for", -- The measure represents the number of audits conducted to ensure compliance with milk sales rules and regulations. Milk Marketing Board auditors review these reports to determine if a milk dealer has made proper advance and final payments to Pennsylvania producers. The auditor review verifies the amount of producer milk purchased and how the producer milk was used. Once the accuracy of the reported information is determined the auditor then can properly assess the minimum value of the producer milk. Any payments found to be inadequate are required to be included in the next month’s payment. The audits of the producer valuation and payment process provide assurance to Pennsylvania dairy farmers that they a being paid properly.
"budget_book_budget_year", -- This is the State Fiscal Year when the program measure numbers in this row were submitted for the Governor's Executive Budget Book.
"fiscal_year", -- Fiscal year for which the program measure values in this row are applicable. Fiscal Years 2021-22 and 2022-23 are estimated amounts based on agency projections.
"general_and_cost_replacement", -- This measure represents the number of general and cost replacement hearings held to determine dealer and retailer costs. These costs are based on the weighted average costs of a representative cross section of milk dealers doing business in each of the areas.
"_100_compliance_with_producer", -- This measure represents the percentage of compliance with the Milk Producers’ Security Act, which provides protection for milk producers against non-payment by milk dealers. Throughout the year auditors check each dealer’s bond amount posted against the dealer’s producer payment obligation. When a dealer’s audited monthly producer obligation exceeds the amount of bond posted, the Director of Enforcement and Staff Attorney review the data and determine if a mid-year bond increase is required.
"percentage_of_producer" -- This metric is calculated by obtaining the value of all licensed dealer payments to producers accurately and on time and dividing that value by the total value of all payments made to or due to producers.
FROM
"pa-gov/governors-executive-budget-program-measures-sfy-d2fn-fwqd:latest"."governors_executive_budget_program_measures_sfy"
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 pa-gov/governors-executive-budget-program-measures-sfy-d2fn-fwqd 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 pa-gov/governors-executive-budget-program-measures-sfy-d2fn-fwqd: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 pa-gov/governors-executive-budget-program-measures-sfy-d2fn-fwqdCheckout 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 pa-gov/governors-executive-budget-program-measures-sfy-d2fn-fwqd:latestThis will download all the objects for the latest tag of pa-gov/governors-executive-budget-program-measures-sfy-d2fn-fwqd 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 pa-gov/governors-executive-budget-program-measures-sfy-d2fn-fwqd: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 pa-gov/governors-executive-budget-program-measures-sfy-d2fn-fwqd: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, pa-gov/governors-executive-budget-program-measures-sfy-d2fn-fwqd is just another Postgres schema.