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 cityparish_expenditures table in this repository, by referencing it like:
"brla-gov/cityparish-expenditures-vwa8-ps2a:latest"."cityparish_expenditures"or in a full query, like:
SELECT
":id", -- Socrata column ID
"source_document_type", -- P = Purchase Order; C = Contract
"vendor_type", -- Indicates the type of business the vendor is in
"commodity_description", -- Description classifying the type of good/service being purchased.
"purchasing_department", -- The department making the purchase
"expense_category", -- Description of the expenditure type.
"invoice_line_item_description", -- A description of the specific expenditure for the corresponding invoice.
"invoice_line_item_amount", -- The total value requested for payment through the invoice.
"check_number", -- The numerical value of the check issued to pay the vendor for the expenditure.
"function", -- The function/purpose of the fund used to pay the expenditure.
"function_id", -- The numerical value of the function/purpose of the fund used to pay the expenditure.
"department", -- The name of the department under which the expenditure is authorized and recorded.
"fund", -- The budgetary name of the fund utilized to pay the expenditure.
"vendor_city",
"source_document_description", -- A description of the purchase order or contract.
"invoice_number", -- The id associated with the vendor's invoice that itemizes justification for payment.
"check_date", -- The date the check was issued to the vendor.
"program_id", -- The numerical value of the program of the fund used to pay the expenditure.
"department_id", -- The numerical value of the department under which the expenditure is authorized and recorded.
"vendor_name_1", -- Vendor's primary business name
"purchasing_department_id", -- ID indicating the department making the purchase
"expense_category_id", -- The numerical value of the expenditure type used to track and classify types of expenditures within the City-Parish financial system.
"division", -- The name of the division (within the department) under which the expenditure is authorized and recorded.
"division_id", -- The numerical value of the division (within the department) under which the expenditure is authorized and recorded.
"program", -- The program of the fund used to pay the expenditure.
"source_document_number", -- The purchase order or contract number of the document used to procure the goods or services.
"subprogram_id", -- The numerical value of the subprogram of the fund used to pay the expenditure.
"disadvantaged", -- Disadvantaged business enterprise
"ethnicity",
"vendor_zip",
"payment_status", -- Status of payment (Cleared and Not Cleared).
"sb_woman", -- Small business woman owned
"invoice_status", -- Status of the invoice P = Paid or V = Voided
"gender",
"commodity_code", -- Code classifying the type of good/service being purchased.
"year", -- The year in which the expenditure was recorded.
"sb_disabled_vet", -- Small business disabled veteran
"vendor_state",
"invoice_date", -- The date the invoice was issued to the City-Parish for processing and payment.
"sb_minority", -- Small business minority owned
"sb_minority_woman", -- Small business minority woman owned
"class", -- The vendor's classification (LLC, Corporation, Sole Proprietor, etc)
"line_number", -- Line number of the specific expenditure for the corresponding invoice.
"fund_id", -- The numerical value of the fund utilized to pay the expenditure.
"journal_entry_period", -- The month in which the expenditure was recorded.
"independent_contractor",
"sb_disadvantaged", -- Small business disadvantaged business enterprise
"vendor_name_2", -- Vendor doing business as (DBA) name
"subprogram", -- The subprogram of the fund used to pay the expenditure.
"geographic_area", -- Geographic area of vendor (INP=In EBR Parish, INS=In State, USA=In Country, INTL=International
"sb_veteran", -- Small business veteran owned
"sb_non_minority", -- Small business non-minority owned
"disabled_veteran", -- Disabled veteran business enterprise
"minority", -- Is the vendor a minority business enterprise
"status", -- Vendor's status A=Active, B=Bidder, I=Inactive, O=One Time Pay, S=Stop, T=Temporary, S=Self Service
"payment_type" -- Type of payment used to pay the vendor (Check, Wire or ACI (P-Cards)).
FROM
"brla-gov/cityparish-expenditures-vwa8-ps2a:latest"."cityparish_expenditures"
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 brla-gov/cityparish-expenditures-vwa8-ps2a 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 brla-gov/cityparish-expenditures-vwa8-ps2a: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 brla-gov/cityparish-expenditures-vwa8-ps2aCheckout 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 brla-gov/cityparish-expenditures-vwa8-ps2a:latestThis will download all the objects for the latest tag of brla-gov/cityparish-expenditures-vwa8-ps2a 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 brla-gov/cityparish-expenditures-vwa8-ps2a: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 brla-gov/cityparish-expenditures-vwa8-ps2a: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, brla-gov/cityparish-expenditures-vwa8-ps2a is just another Postgres schema.