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 environmental_remediation_sites table in this repository, by referencing it like:
"ny-gov/environmental-remediation-sites-c6ci-rzpg:latest"."environmental_remediation_sites"or in a full query, like:
SELECT
":id", -- Socrata column ID
"contaminants", -- Common name of substance/material.
"operator_address1", -- Street address of facility operator.
"program_facility_name", -- Program name of the site.
":@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.
"address2", -- Additional street address or location information for the site.
"locality", -- City, town or village of the address for the site.
"swis_code", -- Four-digit State Wide Information System (SWIS) code identifying the county, and city or town where the site is physically located.
"ou", -- Operable Unit (OU) number.
":@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.
"owner_address1", -- Street 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.
"operator_address2", -- Additional street address information of facility operator.
"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.
"zipcode", -- Zip code of the site. It includes the four digit zip code extension, if available.
"project_name", -- Project Type Name. Identifies phase project is in (i.e., remedial investigation, remedial design, remedial action, etc.).
"disposal_state", -- State for the mailing address of the owner during waste/substance disposal.
"operator_state", -- State for the mailing address of the facility operator.
"address1", -- Street address or location of the site
"county", -- County where site is located.
"operator_city", -- City for the address of the facility operator.
"program_type", -- HW - State Superfund Program; BCP - Brownfield Cleanup Program; VCP - Voluntary Cleanup Program; ERP - Environmental Restoration Program; RCRA – Hazardous Waste Management Program.
"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.
"waste_name", -- Name of waste material (e.g. VOC, PAH).
"owner_name", -- Owner of parcel.
"longitude", -- Y coordinate; blank if unavailable.
"project_completion_date", -- Actual or planned project end date as defined by each program.
"disposal_zip", -- Zip code for the mailing address of the owner during waste/substance disposal.
"control_code", -- Code from Control Codes lookup table. Indicates the type of Control - Environmental Easement, Legacy Control (Deed restriction), or Administrative control.
"georeference", -- Open Data/Socrata-generated geocoding information from supplied address components.
"latitude", -- X coordinate; blank if unavailable.
"operator_name", -- Name of facility operator.
"owner_city", -- City for the address of the owner.
"owner_address2", -- Additional street address information for owner.
"operator_zip", -- Zip code for the mailing address of the facility operator.
"disposal_address2", -- Additional street address information for owner during waste/substance disposal.
"disposal_city", -- City for the address of the owner during waste/substance disposal.
"disposal_address1", -- Street address of the owner during waste/substance disposal.
"disposal_name", -- Owner during waste/substance disposal
"owner_zip", -- Zip code for the mailing address of the owner.
"owner_state", -- State for the mailing address of the owner.
"program_number" -- Program specific site identification number.
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.
This repository is an "external" repository. That means it's hosted elsewhere, in this case at data.ny.gov. When you queryny-gov/environmental-remediation-sites-c6ci-rzpg:latest on the DDN, we "mount" the repository using the socrata mount handler. The mount handler proxies your SQL query to the upstream data source, translating it from SQL to the relevant language (in this case SoQL).
We also cache query responses on the DDN, but we run the DDN on multiple nodes so a CACHE_HIT is only guaranteed for subsequent queries that land on the same node.
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 (like this repository), 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, where the author has pushed Splitgraph Images to the repository, you can "clone" and/or "checkout" the data using sgr cloneand sgr checkout.
Mounting Data
This repository is an external repository. It's not hosted by Splitgraph. It is hosted by data.ny.gov, and Splitgraph indexes it. This means it is not an actual Splitgraph image, so you cannot use sgr clone to get the data. Instead, you can use the socrata adapter with the sgr mount command. Then, if you want, you can import the data and turn it into a Splitgraph image that others can clone.
First, install Splitgraph if you haven't already.
Mount the table with sgr mount
sgr mount socrata \
"ny-gov/environmental-remediation-sites-c6ci-rzpg" \
--handler-options '{
"domain": "data.ny.gov",
"tables": {
"environmental_remediation_sites": "c6ci-rzpg"
}
}'That's it! Now you can query the data in the mounted table like any other Postgres table.
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.