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 new_debt_issuance_for_local_authorities table in this repository, by referencing it like:
"ny-gov/new-debt-issuance-for-local-authorities-qbd7-9grw:latest"."new_debt_issuance_for_local_authorities"or in a full query, like:
SELECT
":id", -- Socrata column ID
"authority_name", -- Name of the Public Authority
"cost_of_issuance", -- The expenses associated with the sale of a new issue of municipal securities, including such items as printing, legal and rating agency fees and others. In certain cases, the underwriter's discount may be considered one of the costs of issuance. This field is blank when the Authority reported having no new debt issuances.
"interest_type", -- Indicates whether the interest rate is fixed or variable. This field is blank when the Authority reported having no new debt issuances.
"bond_closing_date", -- The date of bond issuance. This field is blank when the Authority reported having no new debt issuances.
"issued_debt_obligations", -- Indicates whether the authority reported issuing new debt in a fiscal year. Authorities that report no outstanding debt during the fiscal year are not required to answer this question.
"issue_process", -- Indicates the method of sale used for the new issuance. Authorities may select from the following: Competitive or Negotiated. This field is blank when the Authority reported having no new debt issuances.
"project_name", -- Name of project requiring debt issuance. This field is blank when the Authority reported having no new debt issuances.
"true_interest_cost", -- The effective rate of interest compounded semi-annually on the amount of bonds issued, plus the cost of issuance, expressed as a percentage. This information should be available from the bond counsel, or available from the official statement. This field is blank when the Authority reported having no new debt issuances.
"total_amount", -- Calculated field summing the Refunding Amount and New Amount. This field is blank when the Authority reported having no new debt issuances.
"refunding_amount", -- Total refunding amount. This field is blank when the Authority reported having no new debt issuances.
"new_amount", -- New amount of debt being issued. This field is blank when the Authority reported having no new debt issuances.
"type_of_debt", -- Indicates the type of debt issued. Authorities may select any of the following types of debt: State Guaranteed, State Supported, State Contingent Obligation, State Moral Obligation, Other State-Funded, Authority Debt - General Obligation, Authority Debt – Revenue, Authority Debt – Other, Conduit Debt. Definitions for the different types of debt can be found in the Overview document. This field is blank when the Authority reported having no new debt issuances.
"program", -- Name of the program for which debt was issued. The program is specific to the "Type of Debt" field and correlates to the enacted New York State Budget. This field is only required for State Guaranteed, State Supported, State Contingent Obligation, State Moral Obligation, or Other State-Funded debt. This field is blank when the Authority reported having no new debt issuances or if the debt type is not State-backed debt.
"fiscal_year_end_date", -- Date of Fiscal Year end for the Authority
"term_years" -- The length of the bond (in years) until it matures. This field is blank when the Authority reported having no new debt issuances.
FROM
"ny-gov/new-debt-issuance-for-local-authorities-qbd7-9grw:latest"."new_debt_issuance_for_local_authorities"
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 ny-gov/new-debt-issuance-for-local-authorities-qbd7-9grw 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 ny-gov/new-debt-issuance-for-local-authorities-qbd7-9grw: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 ny-gov/new-debt-issuance-for-local-authorities-qbd7-9grwCheckout 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 ny-gov/new-debt-issuance-for-local-authorities-qbd7-9grw:latestThis will download all the objects for the latest tag of ny-gov/new-debt-issuance-for-local-authorities-qbd7-9grw 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 ny-gov/new-debt-issuance-for-local-authorities-qbd7-9grw: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 ny-gov/new-debt-issuance-for-local-authorities-qbd7-9grw: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, ny-gov/new-debt-issuance-for-local-authorities-qbd7-9grw is just another Postgres schema.