cityofnewyork-us/bid-tabulations-9k82-ys7w
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 bid_tabulations table in this repository, by referencing it like:

"cityofnewyork-us/bid-tabulations-9k82-ys7w:latest"."bid_tabulations"

or in a full query, like:

SELECT 
    ":id", -- Socrata column ID
    "print_time", -- The time that a bid item was printed under the specified title for a Competitive Sealed Bid (“CSB”) solicitation in H:MM format where “H” ranges from 0 – 23. 
    "bidder_name", -- The name of the vendor that submitted a bid under a specified bid title. A vendor may submit a bid for one or more bid items specified in a Competitive Sealed Bid (“CSB”) solicitation.  
    "class_number", -- "A bid can consists of one or more Classes where similar or related items (goods and services) can be grouped into a “Class”. If multiple like items are grouped into a class, awards will be made by class.   Class numbers can range from a blank class (where there is no class or only one class) to two (2) – 99 classes. " 
    "bid_price", -- The unit price, in dollars, for the corresponding bid item submitted by a vendor under the specified bid title. 
    "bid_opening_date", -- The opening date for a Competitive Sealed Bid (“CSB”) solicitation in M/DD/YYYY format. 
    "contact_name", -- The name of the staff at the Department of Citywide Administrative Services (“DCAS”) who was listed as the point of contact on the original Competitive Sealed Bid (“CSB”) solicitation. 
    "print_date", -- The date that a bid item was printed under the specified title for a Competitive Sealed Bid (“CSB”) solicitation in M/DD/YYYY format. 
    "bid_title", -- The title description for a bid solicitation that corresponds to a given bids number a Competitive Sealed Bid (“CSB”) solicitation. A bid title may have more than one (1) bid item associated with it and may be distinguished from other items by its bid item number.  
    "bid_number", -- The seven (7) digit bid number that corresponds to given bid title a Competitive Sealed Bid (“CSB”) solicitation. 
    "bid_item_number", -- The item number associated with the type of good or service listed under a Bid Title. Bid items are assigned consecutive numbers that range from one (1) to 999. 
    "bid_item" -- A description of the unit, or bid item, which is specified in a Competitive Sealed Bid (“CSB”) solicitation. A bid title may have more than one bid item which is distinguished from other items by its bid item number. 
FROM
    "cityofnewyork-us/bid-tabulations-9k82-ys7w:latest"."bid_tabulations"
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/bid-tabulations-9k82-ys7w with SQL in under 60 seconds.

This repository is an "external" repository. That means it's hosted elsewhere, in this case at data.cityofnewyork.us. When you querycityofnewyork-us/bid-tabulations-9k82-ys7w: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.cityofnewyork.us, 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 \
  "cityofnewyork-us/bid-tabulations-9k82-ys7w" \
  --handler-options '{
    "domain": "data.cityofnewyork.us",
    "tables": {
        "bid_tabulations": "9k82-ys7w"
    }
}'

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, cityofnewyork-us/bid-tabulations-9k82-ys7w is just another Postgres schema.

Related Documentation: