colorado-gov/building-permit-counts-in-colorado-v4as-sthd
Icon for Socrata external plugin

Query the Data Delivery Network

Query 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 procotol. 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 building_permit_counts_in_colorado table in this repository, by referencing it like:

"colorado-gov/building-permit-counts-in-colorado-v4as-sthd:latest"."building_permit_counts_in_colorado"

or in a full query, like:

SELECT 
    ":id", -- Socrata column ID
    "vacanthousingunits", -- The estimated number of housing units that have no one living in them
    "occupiedhousingunits", -- The estimated number of housing units that have someone living in them
    "totalhousingunits", -- The estimated total number of housing units
    "personsperhousehold", -- The number of residents estimated per housing unit; excludes group quarters populations.
    "householdpopulation", -- The estimated number of residents living in a place excluding those living in group quarters (like barracks, dorms, or prisons) . To get the group quarter population, use the difference between Total and Household population
    "totalpopulation", -- Indicates the total population estimated as residing in a specific place
    "sdobuildingpermit", -- Indicates the number of building permits reported by local governments to the State Demography Office
    "cbbuildingpermit", -- Refers to the number of building permits reported by the Census Bureau each year
    "year", -- Year associated with collected data
    "area", -- This variable provides the name of each place and indicates if you are looking at a “part” or the “total” for multi-county places. County names are in all-caps.
    "placefips", -- Assigned to cities and towns in alphabetical order so that Aguilar has the lowest PlaceFIPS code (00760) and the City of Yuma has the highest PlaceFIPS code (86750).
    "countyfips" -- Assigned to counties in alphabetical order so that Adams County has the lowest CountyFIPS code (001) and Yuma County has the highest CountyFIPS code (125). Code 999 indicates a multi-county place.
FROM
    "colorado-gov/building-permit-counts-in-colorado-v4as-sthd:latest"."building_permit_counts_in_colorado"
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 colorado-gov/building-permit-counts-in-colorado-v4as-sthd with SQL in under 60 seconds.

This repository is an "external" repository. That means it's hosted elsewhere, in this case at data.colorado.gov. When you querycolorado-gov/building-permit-counts-in-colorado-v4as-sthd: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

Install Splitgraph Locally
bash -c "$(curl -sL https://github.com/splitgraph/splitgraph/releases/latest/download/install.sh)"
 

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.colorado.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 \
  "colorado-gov/building-permit-counts-in-colorado-v4as-sthd" \
  --handler-options '{
    "domain": "data.colorado.gov",
    "tables": {
        "building_permit_counts_in_colorado": "v4as-sthd"
    }
}'

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, colorado-gov/building-permit-counts-in-colorado-v4as-sthd is just another Postgres schema.

Related Documentation: