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 department_of_economic_and_community_development table in this repository, by referencing it like:
"ct-gov/department-of-economic-and-community-development-xnw3-nytd:latest"."department_of_economic_and_community_development"or in a full query, like:
SELECT
":id", -- Socrata column ID
"geocoded_location_zip",
"geocoded_location_state",
"geocoded_location_city",
"geocoded_location_address",
"geocoded_location",
"location_1", -- Address information used for mapping.
"full_time_ct_employment_at_6_30_18", -- Employment numbers are reported to DECD by the company in an annual job survey. All numbers are as of 6/30/19 except MAA- First Five companies which are as of 5/31/19.
"per_application_full_time_jobs_to_be_created_in_ct", -- Employment levels provided by the Company at time of Application.
"per_application_existing_full_time_jobs_in_ct", -- Employment levels provided by the Company at time of Application.
"forgiveness_earned_if_applicable", -- Amount of loan forgiven if contractual employment requirements are met.
"penalty_if_applicable", -- Penalty imposed on a Company for failing to meet its contractual employment obligation. Typically , it is an interest rate increase or specific dollar amount to be repaid.
"job_obligation_status", -- Did the Company meet its employment obligation? Did the Company not meet its employment obligation? Is the Company's contractual job obligation still pending?
"actual_jobs_at_time_of_review", -- Actual jobs created and/or retained as determined by DECD job review or by outside accounting firm review.
"per_contract_part_time_ct_jobs_to_be_created",
"per_contract_part_time_ct_jobs_to_be_retained",
"per_contract_full_time_ct_jobs_to_be_created", -- Contractual obligation for job creation.
"per_contract_full_time_ct_jobs_to_be_retained", -- Contractual obligation for job retention.
"statutory_reference", -- Location of legal authority for which the funding and program requirements are provided.
"funding_source", -- Name of State business assistance program.
"amount_leveraged", -- Amount of non-DECD funding for the project.
"total_project_cost", -- Total amount of DECD and non-DECD funding being used to complete the project.
"total_assistance", -- Total amount of DECD funding being provided to the Company.
"loan_amount", -- Amount of DECD loan funding being provided to the Company.
"grant_amount", -- Amount of DECD grant funding being provided to the Company.
"contract_execution_date", -- If applicable, this date represents the date the contract was signed by the DECD Commissioner.
"woman_minority_veteran_international_export", -- Indicates if Company is 51% minority-owned, woman-owned, or veteran-owned, or if the Company is engaged heavily in international exporting.
"naics_code", -- North American Industry Classification System
"business_industry", -- Business Activity of the Company.
"zip_code", -- Company location
"state",
"county_1",
"municipality", -- Town, city, borough
"company_address", -- Company location
"company_name", -- Entity receiving financial assistance from DECD. Companies with an “*” also received Urban and Industrial Site Reinvestment Tax Credit.
"fiscal_year", -- Based on State Fiscal Year in which the contract was signed, i.e. July 1 to June 30..
":@computed_region_m4y2_whse",
":@computed_region_nhmp_cq6b",
":@computed_region_dam5_q64j",
":@computed_region_snd5_k6zv",
"per_application_part_time_jobs_to_be_created_in_ct", -- Employment levels provided by the Company at time of Application.
"per_application_existing_part_time_jobs_in_ct" -- Employment levels provided by the Company at time of Application.
FROM
"ct-gov/department-of-economic-and-community-development-xnw3-nytd:latest"."department_of_economic_and_community_development"
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 ct-gov/department-of-economic-and-community-development-xnw3-nytd with SQL in under 60 seconds.
This repository is an "external" repository. That means it's hosted elsewhere, in this case at data.ct.gov. When you queryct-gov/department-of-economic-and-community-development-xnw3-nytd: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.ct.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 \
"ct-gov/department-of-economic-and-community-development-xnw3-nytd" \
--handler-options '{
"domain": "data.ct.gov",
"tables": {
"department_of_economic_and_community_development": "xnw3-nytd"
}
}'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, ct-gov/department-of-economic-and-community-development-xnw3-nytd is just another Postgres schema.