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 nyc_free_tax_prep_sites table in this repository, by referencing it like:
"cityofnewyork-us/nyc-free-tax-prep-sites-5kqf-fg3n:latest"."nyc_free_tax_prep_sites"or in a full query, like:
SELECT
":id", -- Socrata column ID
"thursdayopen", -- Opening time in regular time format
"longitude", -- Longitude of the service site's physical loation
"wednesdayclose", -- Closing time in regular time format
"saturdayopen", -- Opening time in regular time format
"fridayclose", -- Closing time in regular time format
"ianydayopen", -- Minumum opening hour including all days of operation supporting map-filtering logic
"fridayopen", -- Opening time in regular time format
"iwednesdayclose", -- Number representing the hour the site closes (24-hour clock)
"notes",
"sundayclose", -- Closing time in regular time format
"sitekey", -- An Identification Number assigned to tax preparation sites for internal tracking.
"sundayopen", -- Opening time in regular time format
"isundayclose", -- Number representing the hour the site closes (24-hour clock)
"latitude", -- Latitude of the service site's physical location
"ycoordinate", -- Mapping Ycoordinate of the service site's physical location
"ithursdayclose", -- Number representing the hour the site closes (24-hour clock)
"bbl", -- Borough-Block-Lot number of the service site's physical location
"ianydayclose", -- Maximum closing hour including all days of operation supporting map-filtering logic
"building", -- The building number of the service site's physical location
"scheduleexceptions", -- Exceptions to the posted schedule, typically holidays where services are not available
"communitydistrict", -- Community District of the service site's physical location
"nta", -- Neighborhood Tabulation Area of the service site's physical location
":@computed_region_yeji_bk3q",
":@computed_region_f5dn_yrer",
"xcoordinate", -- Mapping Xcoordinate of the service site's physical location
"providername", -- Name of the organization providing free tax preparation services
":@computed_region_sbqj_enih",
"sitename", -- Name of the specific site where services can be obtained
"sitestatus", -- Name of the organization providing free tax preparation services; "Active = Site is currently active Concluded = The site is not currently providing services Sites will only display on the map when SiteStatus = 'Active' and ShowOnMap = 'Yes'."
":@computed_region_efsh_h5xi",
"extension", -- Phone Extension
"show311", -- Indicator of whether the site should be displayed on the map; Yes; No
"mappedaddress", -- A concatenation of the service site's physical address used for map display purposes
"phone", -- Primary phone number of the service provider
"imondayopen", -- Number representing the hour the site opens (24-hour clock)
"icon", -- Type of icon to display on the map - supports front-end rendering on the map
"postcode", -- The postal code of the service site's physical address
"borough", -- The borough of the service site's physical address
"closedateiso", -- The closing date for the NYC Free Tax Prep site, in International Organization for Standardization (ISO-8601) format.
"amendedreturn", -- Indicator for whether the NYC Free Tax Prep site can help you with filing amended returns; Yes; No
"itin", -- Indicator for whether the NYC Free Tax Prep site can help you with your Individual Taxpayer Identification Number (ITIN) application.
"ada_accessible", -- Indicator of whether the service site is ADA accessible; Yes; No
"geocoded_column_address",
"incomelimit", -- Income limit, if any, to qualify for NYC Free Tax Prep service.
"showonmap", -- Indicator of whether the site should be displayed on the map; Yes; No
"website", -- Website of the service provider
"opendateiso", -- The starting date the NYC Free Tax Prep site opens to eligible New Yorkers, in International Organization for Standardization (ISO-8601) format.
"s1", -- The tax preparation service options available at the NYC Free Tax Prep site; In Person = An IRS certified VITA/TCE volunteer preparer will help you complete your return; Drop-off = You can drop off your tax documents and pick up the completed return later; Assisted Self-Preparation = Complete your tax return online with help from an IRS certified VITA/TCE preparer.
"closedatestr", -- The closing date for the NYC Free Tax Prep site.
"selfemployed", -- Indicator for whether the NYC Free Tax Prep site can help if you are self-employed; Yes; No
"opendatestr", -- The starting date the NYC Free Tax Prep site opens to eligible New Yorkers.
"prioryear", -- Indicator for whether the NYC Free Tax Prep site can help you with filing returns for previous tax years; Yes; No
"aarp", -- Indicator for whether the NYC Free Tax Prep site can help if you are a senior over age 60 years with pension or retirement-related questions; Yes; No
"tuesdayclose", -- Closing time in regular time format
"tuesdayopen", -- Opening time in regular time format
"saturdayclose", -- Closing time in regular time format
"mondayclose", -- Closing time in regular time format
":@computed_region_92fq_4b7q",
"isaturdayclose", -- Number representing the hour the site closes (24-hour clock)
"ifridayclose", -- Number representing the hour the site closes (24-hour clock)
"mondayopen", -- Opening time in regular time format
"isaturdayopen", -- Number representing the hour the site opens (24-hour clock)
"thursdayclose", -- Closing time in regular time format
"citycouncildistrict", -- Council District of the service site's physical location
"unit", -- Floor, Suite, or sub-unit of the service site's physical address.
"city", -- The City of the service site's physical address
"ituesdayclose", -- Number representing the hour the site closes (24-hour clock)
"l1", -- The languages available at the NYC Free Tax Prep site.
"geocoded_column_zip",
"isundayopen", -- Number representing the hour the site opens (24-hour clock)
"ithursdayopen", -- Number representing the hour the site opens (24-hour clock)
"imondayclose", -- Number representing the hour the site closes (24-hour clock)
"wednesdayopen", -- Opening time in regular time format
"apptorwalkin", -- Indicator of whether NYC Free Tax Prep site requires appointment, accepts walk-ins, or both.
"ituesdayopen", -- Number representing the hour the site opens (24-hour clock)
"ifridayopen", -- Number representing the hour the site opens (24-hour clock)
"iwednesdayopen", -- Number representing the hour the site opens (24-hour clock)
"geocoded_column",
"geocoded_column_state",
"street", -- The street name of the service site's physical address
"geocoded_column_city"
FROM
"cityofnewyork-us/nyc-free-tax-prep-sites-5kqf-fg3n:latest"."nyc_free_tax_prep_sites"
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/nyc-free-tax-prep-sites-5kqf-fg3n 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/nyc-free-tax-prep-sites-5kqf-fg3n: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/nyc-free-tax-prep-sites-5kqf-fg3nCheckout 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/nyc-free-tax-prep-sites-5kqf-fg3n:latestThis will download all the objects for the latest tag of cityofnewyork-us/nyc-free-tax-prep-sites-5kqf-fg3n 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/nyc-free-tax-prep-sites-5kqf-fg3n: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/nyc-free-tax-prep-sites-5kqf-fg3n: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/nyc-free-tax-prep-sites-5kqf-fg3n is just another Postgres schema.