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 building_and_safety_temporary_special_event_tse table in this repository, by referencing it like:
"lacity/building-and-safety-temporary-special-event-tse-8spw-3fhx:latest"."building_and_safety_temporary_special_event_tse"or in a full query, like:
SELECT
":id", -- Socrata column ID
"work_desc", -- Describes the work to be performed under the permit application.
"address_start", -- Beginning house number of property address on permit application. Example 1: For "200 - 200 N Main Ave", Address Start is 200. Example 2: For "202 1/4 - 204 1/2 N Main St SE", Address Start is 202.
"permitno", -- This is the permit number assigned by the Plan Check and Inspection System as soon as an application for a permit has been filed. Before a permit is issued, the number is known as the Application Number. After the permit is issued, this same number becomes the Permit Number.
"location", -- Additional information on the location of the temporary special event.
"addr_name", -- Street name of property address for permit application.
"lat_lon_state",
"event_end_date", -- Ending date of the temporary special event.
"addr_dir", -- Street direction of property address for permit application. Example 1: For "200 - 200 Main Ave", Street Direction is null. Example 2: For "202 1/4 - 204 1/2 N Main St SE", Street Direction is N.
"addr_frac_start", -- Beginning fraction of property address on permit application. Example 1: For "200 - 200 N Main Ave", Address Fraction Start is null. Example 2: For "202 1/4 - 204 1/2 N Main St SE", Address Fraction Start is 1/4.
"per_type", -- The type of permit application. For this dataset, Permit Type defaults to Temporary Special Event.
"lat_lon_address",
"addr_suff_dir", -- Street suffix direction of property address for permit application. Example 1: For "200 - 200 N Main Ave", Suffix Direction is null. Example 2: For "202 1/4 - 204 1/2 N Main St SE", Suffix Direction is SE.
"addr_suff", -- Street suffix of property address for permit application. Example 1: For "200 - 200 Main Ave", Street Suffix is Ave. Example 2: For "202 1/4 - 204 1/2 N Main St SE", Street Suffix is St.
"event_start_date", -- Starting date of the temporary special event.
"addr_unit_end", -- Ending unit number of property address on permit application. Example 1: For "200 - 200 N Main Ave, #1-#8", Unit Range End is #8. Example 2: For "202 1/4 - 204 1/2 N Main St SE", Unit Range End is null.
"lat_lon_zip",
"addr_unit_start", -- Beginning unit number of property address on permit application. Example 1: For "200 - 200 N Main Ave, #1-#8", Unit Range Start is #1. Example 2: For "202 1/4 - 204 1/2 N Main St SE", Unit Range Start is null.
"addr_frac_end", -- Ending house number fraction of property address on permit application. Example 1: For "200 - 200 N Main Ave", Address Fraction End is null. Example 2: For "202 1/4 - 204 1/2 N Main St SE", Address Fraction End is 1/2.
"per_sub_type", -- The permit sub-type determines whether the permit application is for a 1 or 2 family dwelling, a multi-family dwelling, or a commercial structure.
"lat_lon_city",
"event_name", -- Name of the temporary special event.
"zip_code", -- Zip code of property address for permit application.
"address_end", -- Ending house number of property address on permit application. Example 1: For "200 - 200 N Main Ave", Address End is 200. Example 2: For "202 1/4 - 204 1/2 N Main St SE", Address End is 204.
":@computed_region_2dna_qi2s",
":@computed_region_tatf_ua23",
":@computed_region_k96s_3jcv",
":@computed_region_kqwf_mjcx",
":@computed_region_qz3q_ghft",
":@computed_region_ur2y_g4cx",
"lat_lon" -- GPS location point.
FROM
"lacity/building-and-safety-temporary-special-event-tse-8spw-3fhx:latest"."building_and_safety_temporary_special_event_tse"
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/building-and-safety-temporary-special-event-tse-8spw-3fhx 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/building-and-safety-temporary-special-event-tse-8spw-3fhx: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/building-and-safety-temporary-special-event-tse-8spw-3fhxCheckout 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/building-and-safety-temporary-special-event-tse-8spw-3fhx:latestThis will download all the objects for the latest tag of lacity/building-and-safety-temporary-special-event-tse-8spw-3fhx 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/building-and-safety-temporary-special-event-tse-8spw-3fhx: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/building-and-safety-temporary-special-event-tse-8spw-3fhx: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/building-and-safety-temporary-special-event-tse-8spw-3fhx is just another Postgres schema.