Query the Data Delivery NetworkQuery the DDN
The 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
environmental_remediation_sites table in this repository, by referencing it like:
or in a full query, like:
SELECT ":id", -- Socrata column ID ":@computed_region_yamh_8v7k", -- This column was automatically created in order to record in what polygon from the dataset 'NYS Municipal Boundaries' (yamh-8v7k) the point in column 'georeference' is located. This enables the creation of region maps (choropleths) in the visualization canvas and data lens. "disposal_address1", -- Street address of the owner during waste/substance disposal. "owner_city", -- City for the address of the owner. "latitude", -- X coordinate; blank if unavailable. "locality", -- City, town or village of the address for the site. "control_code", -- Code from Control Codes lookup table. Indicates the type of Control - Environmental Easement, Legacy Control (Deed restriction), or Administrative control. "program_type", -- HW - State Superfund Program; BCP - Brownfield Cleanup Program; VCP - Voluntary Cleanup Program; ERP - Environmental Restoration Program; RCRA – Hazardous Waste Management Program. "disposal_zip", -- Zip code for the mailing address of the owner during waste/substance disposal. "disposal_city", -- City for the address of the owner during waste/substance disposal. "owner_zip", -- Zip code for the mailing address of the owner. "operator_zip", -- Zip code for the mailing address of the facility operator. "operator_state", -- State for the mailing address of the facility operator. "owner_state", -- State for the mailing address of the owner. "control_type", -- Type of control - Institutional or Engineering. ":@computed_region_kjdx_g34t", -- This column was automatically created in order to record in what polygon from the dataset 'Counties' (kjdx-g34t) the point in column 'georeference' is located. This enables the creation of region maps (choropleths) in the visualization canvas and data lens. ":@computed_region_wbg7_3whc", -- This column was automatically created in order to record in what polygon from the dataset 'New York Zip Codes' (wbg7-3whc) the point in column 'georeference' is located. This enables the creation of region maps (choropleths) in the visualization canvas and data lens. "owner_name", -- Owner of parcel. "waste_name", -- Name of waste material (e.g. VOC, PAH). "project_completion_date", -- Actual or planned project end date as defined by each program. "ou", -- Operable Unit (OU) number. "county", -- County where site is located. "address1", -- Street address or location of the site "siteclass", -- Alpha-numeric code that identifies the site class or status: 02 - The disposal of hazardous waste represents a significant threat to the environment or to health; 03 - Contamination does not presently constitute a significant threat the environment or to health; 04 - The site has been properly closed but that requires continued site management; 05 - No further action required; A - Active; C - Completed; P - Sites where preliminary information indicates that a site may have contamination; PR - Sites that are, or have been, subject to the requirements of the RCRA; N - No further action. "program_facility_name", -- Program name of the site. "project_name", -- Project Type Name. Identifies phase project is in (i.e., remedial investigation, remedial design, remedial action, etc.). "operator_address2", -- Additional street address information of facility operator. "operator_name", -- Name of facility operator. "disposal_address2", -- Additional street address information for owner during waste/substance disposal. "dec_region", -- NYSDEC Region where the site is located: Region 1: (Long Island) Nassau and Suffolk counties; Region 2: (New York City) Brooklyn, Bronx, Manhattan, Queens and Staten Island; Region 3: (Lower Hudson Valley) Dutchess, Orange, Putnam, Rockland, Sullivan, Ulster and Westchester counties; Region 4: (Capital Region/Northern Catskills) Albany, Columbia, Delaware, Greene, Montgomery, Otsego, Rensselaer, Schenectady and Schoharie counties; Region 5: (Eastern Adirondacks/Lake Champlain) Clinton, Essex, Franklin, Fulton, Hamilton, Saratoga, Warren and Washington counties; Region 6: (Western Adirondacks/Eastern Lake Ontario) Herkimer, Jefferson, Lewis, Oneida and St. Lawrence counties; Region 7: (Central New York) Broome, Cayuga, Chenango, Cortland, Madison, Onondaga, Oswego, Tioga and Tompkins counties; Region 8: (Western Finger Lakes) Chemung, Genesee, Livingston, Monroe, Ontario, Orleans, Schuyler, Seneca, Steuben, Wayne and Yates counties; Region 9: (Western New York) Allegany, Chautauqua, Cattaraugus, Erie, Niagara and Wyoming counties. "swis_code", -- Four-digit State Wide Information System (SWIS) code identifying the county, and city or town where the site is physically located. "address2", -- Additional street address or location information for the site. "operator_city", -- City for the address of the facility operator. "disposal_state", -- State for the mailing address of the owner during waste/substance disposal. "owner_address2", -- Additional street address information for owner. "owner_address1", -- Street address of the owner. "longitude", -- Y coordinate; blank if unavailable. "zipcode", -- Zip code of the site. It includes the four digit zip code extension, if available. "program_number", -- Program specific site identification number. "operator_address1", -- Street address of facility operator. "disposal_name", -- Owner during waste/substance disposal "contaminants", -- Common name of substance/material. "georeference" -- Open Data/Socrata-generated geocoding information from supplied address components. FROM "ny-gov/environmental-remediation-sites-c6ci-rzpg:latest"."environmental_remediation_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
ny-gov/environmental-remediation-sites-c6ci-rzpg 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
ny-gov/environmental-remediation-sites-c6ci-rzpg: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
This will be quick, and does not download the actual data.
sgr clone ny-gov/environmental-remediation-sites-c6ci-rzpg
Checkout the data
Once you've cloned the data, you need to "checkout" the tag that you want. For example, to checkout the
sgr checkout ny-gov/environmental-remediation-sites-c6ci-rzpg:latest
This will download all the objects for the
latest tag of
ny-gov/environmental-remediation-sites-c6ci-rzpg 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/environmental-remediation-sites-c6ci-rzpg: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/environmental-remediation-sites-c6ci-rzpg:latest
This 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/environmental-remediation-sites-c6ci-rzpg is just another Postgres schema.