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 tax_increment_financing_tif_annual_report_itemized table in this repository, by referencing it like:
"cityofchicago/tax-increment-financing-tif-annual-report-itemized-umwj-yc4m:latest"."tax_increment_financing_tif_annual_report_itemized"or in a full query, like:
SELECT
":id", -- Socrata column ID
"interest_cost", -- Costs of interest incurred by developer related to the construction, renovation, or rehabilitation of a redevelopment project.
"tif_district", -- Redevelopment project area
"relocation_costs", -- Costs incurred during the course of moving to a new residence.
"report_year", -- Calendar year to which the record applies
"renovation_rehab_etc", -- Costs of renovation, rehabilitation, reconstruction, and repair of existing public or private buildings within a redevelopment project area.
"site_preparation_costs", -- Costs for land clearing to prepare the building site.
"library_districts", -- Costs of reimbursing library districts for their increased costs caused by TIF assisted housing projects.
"capital_costs", -- Fixed, one-time expenses incurred on the purchase of land, buildings, construction, and equipment used in the rendering of services.
"removing_contaminants", -- Costs of eliminating or removing contaminants and other impediments.
"administrative_cost", -- Costs associated with general administration of the business.
"other", -- Any other form of expense not clearly categorized.
"cost_of_studies", -- Implementation and administration of the redevelopment plan, staff, and professional service cost
"day_care_services", -- Costs associated with day care services for children of employees from low -income families working for businesses located within TIF area.
"marketing_sites", -- Amount of money spent on marketing.
"new_housing", -- Costs of construction of new housing units for low-income or very-low-income households.
"tif_number", -- The unique, numeric ID assigned to the TIF district.
"financing_costs", -- Cost, interest, and other charges involved in the borrowing of money to build or purchase assets.
"job_training_retraining", -- Costs of job training, retraining, advanced-vocational, or career education.
"job_training", -- Costs of job training and retraining projects.
"in_lieu_of_taxes", -- A payment made to compensate a government for some or all the property tax revenue lost due to tax exempt ownership or use of a real property.
"school_districts", -- Costs of reimbursing school districts for their increased costs caused by TIF assisted housing projects.
"public_works" -- Costs of construction of public works or improvements.
FROM
"cityofchicago/tax-increment-financing-tif-annual-report-itemized-umwj-yc4m:latest"."tax_increment_financing_tif_annual_report_itemized"
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 cityofchicago/tax-increment-financing-tif-annual-report-itemized-umwj-yc4m 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 sgr cloneand sgr checkout.
Cloning Data
Because cityofchicago/tax-increment-financing-tif-annual-report-itemized-umwj-yc4m: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 sgr clone
This will be quick, and does not download the actual data.
sgr clone cityofchicago/tax-increment-financing-tif-annual-report-itemized-umwj-yc4mCheckout the data
Once you've cloned the data, you need to "checkout" the tag that you want. For example, to checkout the latest tag:
sgr checkout cityofchicago/tax-increment-financing-tif-annual-report-itemized-umwj-yc4m:latestThis will download all the objects for the latest tag of cityofchicago/tax-increment-financing-tif-annual-report-itemized-umwj-yc4m 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 cityofchicago/tax-increment-financing-tif-annual-report-itemized-umwj-yc4m: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 cityofchicago/tax-increment-financing-tif-annual-report-itemized-umwj-yc4m:latestThis 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, cityofchicago/tax-increment-financing-tif-annual-report-itemized-umwj-yc4m is just another Postgres schema.