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 listing_of_active_businesses table in this repository, by referencing it like:
"lacity/listing-of-active-businesses-6rrh-rzua:latest"."listing_of_active_businesses"or in a full query, like:
SELECT
":id", -- Socrata column ID
"zip_code", -- Zip code of the business location.
"location_1_city",
"location_1", -- Latitude & Longitude, if present, for this business location.
"location_1_zip",
"location_end_date", -- The most recent end date of all business activities at the location.
"location_start_date", -- The start date of the first business activity registered at this location.
"council_district", -- The council district # reflects the current council district assignment for that location address. "0" means the business location is out of the City.
"primary_naics_description", -- Description of the primary NAICS code. Descriptions that are noted as "(1997 NAICS)" apply the code and description designated in 1997 as referred to in the New Business Exemption Ordinance.
"naics", -- The self-reported North American Industry Classification System (NAICS) code, which is used in classifying business establishments.
"mailing_city", -- Mailing address city of the business.
"mailing_address", -- Mailing address of the business.
"location_description", -- Abbreviated address description of the business location.
"city", -- City of the business location.
"street_address", -- Street address of the business location.
"dba_name", -- Doing Business As (DBA) name. If more than one DBA name exists, then all names are shown as a pipe-separated list.
"business_name", -- The legal name of the business.
"location_1_state",
"mailing_zip_code", -- Mailing address Zip code of the business.
"location_1_address",
"location_account", -- The account number of the business location.
":@computed_region_ur2y_g4cx",
":@computed_region_qz3q_ghft",
":@computed_region_tatf_ua23",
":@computed_region_2dna_qi2s",
":@computed_region_kqwf_mjcx",
":@computed_region_k96s_3jcv"
FROM
"lacity/listing-of-active-businesses-6rrh-rzua:latest"."listing_of_active_businesses"
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 lacity/listing-of-active-businesses-6rrh-rzua 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 lacity/listing-of-active-businesses-6rrh-rzua: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 lacity/listing-of-active-businesses-6rrh-rzuaCheckout 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 lacity/listing-of-active-businesses-6rrh-rzua:latestThis will download all the objects for the latest tag of lacity/listing-of-active-businesses-6rrh-rzua 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 lacity/listing-of-active-businesses-6rrh-rzua: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 lacity/listing-of-active-businesses-6rrh-rzua: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, lacity/listing-of-active-businesses-6rrh-rzua is just another Postgres schema.