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 vendor_payments table in this repository, by referencing it like:
"fultoncountyga-gov/vendor-payments-mxhc-krcg:latest"."vendor_payments"or in a full query, like:
SELECT
":id", -- Socrata column ID
"vendor_invoice_date", -- The date the invoice was received from the vendor
"unit_name", -- The name of the business unit within the department making the payment
"disb_date", -- The date on which the payment was made
"unit", -- An alphanumeric code used within the financial system to identify the business unit within the department making the payment
"object_name", -- The category of goods or services into which the payment falls (e.g., Professional Services, Printing, Office Supplies)
"dis_doc_id",
"fiscal_year", -- The fiscal year in which the payment was made
"dept", -- An alphanumeric code used within the financial system to identify the department making the payment
"department_name", -- The name of the department making the payment
"fund", -- An alphanumeric code used within the financial system to identify the fund from which the payment was made
"fund_name", -- The name of the fund from which the payment was made (e.g., General Fund, Water and Sewer Fund)
"amount", -- The amount of the payment in U.S. dollars.
"vendor_legal_name", -- The legal name of the vendor
"vendor_invoice_no", -- The number of the invoice
"fy_period", -- A numeric indicator of the month in which the payment was made (1=Janaury, 2=February, etc.)
"check_clearance_or_cancel_date", -- The date the check was cleared or cancelled.
"check_cc_week",
"vendor_invoice_week",
"payment_document",
"disb_week",
"check_no", -- The number of the check used to make the payment
"vendor_code", -- An internally generated code uniquely identifying each vendor. This can be used to join Vendor Payments to the County Vendors dataset containing additional details on each vendor.
"object", -- An alphanumeric code used within the financial system to identify the category into which the payment falls (e.g., Professional Services, Printing, Office Supplies)
"city", -- The city this vendor code is tied to.
"payment_type",
"check_status" -- Indicates whether the check is pending or has been cleared.
FROM
"fultoncountyga-gov/vendor-payments-mxhc-krcg:latest"."vendor_payments"
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 fultoncountyga-gov/vendor-payments-mxhc-krcg 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 fultoncountyga-gov/vendor-payments-mxhc-krcg: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 fultoncountyga-gov/vendor-payments-mxhc-krcgCheckout 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 fultoncountyga-gov/vendor-payments-mxhc-krcg:latestThis will download all the objects for the latest tag of fultoncountyga-gov/vendor-payments-mxhc-krcg 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 fultoncountyga-gov/vendor-payments-mxhc-krcg: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 fultoncountyga-gov/vendor-payments-mxhc-krcg: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, fultoncountyga-gov/vendor-payments-mxhc-krcg is just another Postgres schema.