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 iowa_pandemic_recovery_reporting_payments_to table in this repository, by referencing it like:
"mydata-iowa-gov/iowa-pandemic-recovery-reporting-payments-to-cgm6-jbzf:latest"."iowa_pandemic_recovery_reporting_payments_to"or in a full query, like:
SELECT
":id", -- Socrata column ID
"amount", -- Amount paid to the organization.
"vendor_zip", -- Zip code associated with the physical address of the organization.
"vendor_city", -- City associated with the physical address of the organization.
"object_class_name", -- A description of the type of expenditure.
"fund", -- The name of the fund where payment was made.
"fund_code", -- The four digit code designating the fund expenses were paid from.
"unit", -- The four digit code used to designate the organizational unit within the department associated with the payment.
"fiscal_period", -- Two digit fiscal period associated with the payment (i.e., 1-15).
"budget_fy", -- The four digit budget fiscal year (July 1 - June 30 + holdover) associated with the payment.
"federal_department", -- Name of the Federal Department who awarded the federal funds associated with the payment.
"vendor_legal", -- Legal name for the organization.
"federal_agency", -- Name of the Federal Agency responsible for overseeing the Federal funds associated with this payment.
"geocoded_column", -- Geocoded location is based on the city, state and zip.
"vendor_id", -- Field is a concatenation of the vendor number and vendor legal name without spaces.
"vendor_dba", -- Name organization is doing business as.
"object_class", -- The three digit code used in the state accounting system to designate the type of expenditure.
"unit_name", -- The name of the organizational unit within the department associated with the payment.
"state_dept_no", -- The three digit code used to designate the department associated with the payment (e.g., 413).
"federal_program_title", -- Name of the Federal program that provided the federal funds that supported the payment.
"payment_issue_date", -- Date payment was made.
"record_id", -- Journal record number from the State Accounting System, or other unique identifier created for the record.
"vendor_state", -- State associated with the physical address of the organization.
"letter_of_credit", -- This is the Letter of Credit value associated with the PPC code in the state accounting system that is unique to the federal award.
"state_department", -- Name of the State Department making the payment.
"vendor_number", -- Unique identifier used in the State Accounting System for the vendor.
":@computed_region_g8ff_h7ce",
":@computed_region_y683_txed",
":@computed_region_hhz5_dst4"
FROM
"mydata-iowa-gov/iowa-pandemic-recovery-reporting-payments-to-cgm6-jbzf:latest"."iowa_pandemic_recovery_reporting_payments_to"
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 mydata-iowa-gov/iowa-pandemic-recovery-reporting-payments-to-cgm6-jbzf 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 mydata-iowa-gov/iowa-pandemic-recovery-reporting-payments-to-cgm6-jbzf: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 mydata-iowa-gov/iowa-pandemic-recovery-reporting-payments-to-cgm6-jbzfCheckout 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 mydata-iowa-gov/iowa-pandemic-recovery-reporting-payments-to-cgm6-jbzf:latestThis will download all the objects for the latest tag of mydata-iowa-gov/iowa-pandemic-recovery-reporting-payments-to-cgm6-jbzf 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 mydata-iowa-gov/iowa-pandemic-recovery-reporting-payments-to-cgm6-jbzf: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 mydata-iowa-gov/iowa-pandemic-recovery-reporting-payments-to-cgm6-jbzf: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, mydata-iowa-gov/iowa-pandemic-recovery-reporting-payments-to-cgm6-jbzf is just another Postgres schema.