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 financial_empowerment_centers table in this repository, by referencing it like:
"cityofnewyork-us/financial-empowerment-centers-dt2z-amuf:latest"."financial_empowerment_centers"or in a full query, like:
SELECT
":id", -- Socrata column ID
"council_district", -- Community Board number which represents the Community District or joint interest area where the Financial Empowerment Center is located.
"location_address",
"location", -- Concatenated Latitude and Longitude coordinate location where Financial Empowerment Center is located. In unit of decimal degree
"bin", -- Building Identification Number (BIN) for the building in which the Financial Empowerment Center is located. The BIN is a seven-digit numerical identifier unique to each building in the City of New York. The first digit is the Borough Code. If the borough code is followed by all zeroes (commonly referred to as a ‘million BIN’, this indicates that a BIN has not been assigned.
"host_organization", -- The organization that hosts the Financial Empowerment Center.
"site_location_address", -- The Financial Empowerment Center address with unit information.
"building", -- The building number for the address where the Financial Empowerment Center is located. Note, some building numbers in Queens may include a dash character as part of the number.
"provider", -- Financial counseling service provider that operates the Financial Empowerment Center.
"borough", -- The name of the NYC Borough where the Financial Empowerment Center is located.
"telephone", -- Phone number for booking an appointment at a Financial Empowerment Center.
"census_tract", -- The 2010 US Census Tract where the Financial Empowerment Center is located.
"city", -- USPS preferred city name for the address where the Financial Empowerment Center is located.
"latitude", -- Latitude of the Financial Empowerment Center location.
"y_coordinates", -- The Y Coordinate of the XY coordinate pair where the Financial Empowerment Center is located. NAD 1983 StatePlane New York Long Island FIPS 3104, Unit of measure: Feet
"location_zip",
"location_state",
":@computed_region_f5dn_yrer",
"x_coordinates", -- The X Coordinate of the XY coordinate pair where the Financial Empowerment Center is located. NAD 1983 StatePlane New York Long Island FIPS 3104, Unit of measure: Feet
"nta", -- Neighborhood Tabulation Area (NTA) where Financial Empowerment Center is located.
":@computed_region_efsh_h5xi",
"bbl", -- A concatenation of the borough, block, and lot numbers where Financial Empowerment Center is located. Identifies a parcel of real property in New York City.
"zip_code", -- ZIP code where the Financial Empowerment Center is located.
"community_board", -- Council District number where Financial Empowerment Center is located.
":@computed_region_yeji_bk3q",
":@computed_region_92fq_4b7q",
"hours", -- Financial Empowerment Center typical hours of operation.
"location_city",
"street", -- The street name where the Financial Empowerment Center is located.
"days_open", -- Weekdays when the Financial Empowerment Center financial counseling services are regularly provided.
"language_s", -- Language spoken by financial counselors at the Financial Empowerment Center.
":@computed_region_sbqj_enih",
"longitude" -- Longitude of the Financial Empowerment Center location.
FROM
"cityofnewyork-us/financial-empowerment-centers-dt2z-amuf:latest"."financial_empowerment_centers"
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 cityofnewyork-us/financial-empowerment-centers-dt2z-amuf 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 cityofnewyork-us/financial-empowerment-centers-dt2z-amuf: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 cityofnewyork-us/financial-empowerment-centers-dt2z-amufCheckout 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 cityofnewyork-us/financial-empowerment-centers-dt2z-amuf:latestThis will download all the objects for the latest tag of cityofnewyork-us/financial-empowerment-centers-dt2z-amuf 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 cityofnewyork-us/financial-empowerment-centers-dt2z-amuf: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 cityofnewyork-us/financial-empowerment-centers-dt2z-amuf: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, cityofnewyork-us/financial-empowerment-centers-dt2z-amuf is just another Postgres schema.