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 311_citizen_requests_for_service table in this repository, by referencing it like:
"brla-gov/311-citizen-requests-for-service-7ixm-mnvx:latest"."311_citizen_requests_for_service"or in a full query, like:
SELECT
":id", -- Socrata column ID
"streetnum", -- The street number of the address where services are needed or issues need to be resolved.
"streetaddress", -- The full street address where service are needed or issues need to be resolved.
"crossname", -- Any cross street information available as reported by the submitting citizen (for example, at an intersection).
":@computed_region_qfmj_2fwi",
":@computed_region_ntzg_c2w3",
":@computed_region_8tu6_j4iw",
":@computed_region_hfgy_t898",
"parenttype", -- The parent type of service request - matches that of the ParentID field.
"geolocation_address",
"geolocation",
":@computed_region_92rf_uvyc",
"closeddate", -- The date the service request was closed due to the request as being addressed or the issue being resolved, confirmed by the responding department/division.
"createdate", -- The date the service request was created within the City-Parish's 311 service request and complaint tracking system, either by phone, online, or via web app.
"deptdiv", -- The City-Parish department and division responsible for responding to the requested service or reported issue - matches that of the DeptDivID field.
"streetname", -- The name of the street where services are needed or issues need to be resolved.
"latitude", -- The latitude coordinates of the issue or request for service for geocoding purposes.
"comments", -- Any comments submitted by the reporting citizen associated with the request for service or issue to be resolved.
"deptdivid", -- The ID of the City-Parish department and division responsible for responding to the requested service or reported issue.
"longitude", -- The longitude coordinates of the issue or request for service for geocoding purposes.
"division", -- The City-Parish division responsible for responding to the requested service or reported issue, which is a division of the department noted in the Department field.
"cityname", -- The city of the reported issue - Baton Rouge, Baker, Zachary, or Central. Issues reported in the unincorporated areas of East Baton Rouge Parish or without city information are reported as East Baton Rouge.
"typename", -- A description of the type of service request represented by the request ID - matches that of the TypeID field.
"statusdesc", -- Matches Status ID - Open, Closed, or In Progress.
"id", -- Unique identifier assigned to each citizen request for service for tracking and resolution purposes.
":@computed_region_jrqt_zu77",
":@computed_region_uvg4_nwq8",
":@computed_region_i2e6_956r",
"geolocation_state",
"geolocation_zip",
"status", -- Status of service request 0 = Open, 1 = Closed, 3 = In Progress.
"typeid", -- The specific type of service request represented by the request ID.
"department", -- The City-Parish department with oversight over the requested service or reported issue.
"parentid", -- The parent category ID of the type of service request (typename) as organized within the City-Parish 311 Citizen Request system.
"geolocation_city",
":@computed_region_8siy_mghw",
":@computed_region_tm4z_r3je",
":@computed_region_tqy7_429i",
"lastaction" -- The date of the most recent adjustment or notation to this service request, as noted by the responding department/division. Typically, this field will match that of the closed date if a request has been resolved or closed.
FROM
"brla-gov/311-citizen-requests-for-service-7ixm-mnvx:latest"."311_citizen_requests_for_service"
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/311-citizen-requests-for-service-7ixm-mnvx 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/311-citizen-requests-for-service-7ixm-mnvx: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/311-citizen-requests-for-service-7ixm-mnvxCheckout 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/311-citizen-requests-for-service-7ixm-mnvx:latestThis will download all the objects for the latest tag of brla-gov/311-citizen-requests-for-service-7ixm-mnvx 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/311-citizen-requests-for-service-7ixm-mnvx: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/311-citizen-requests-for-service-7ixm-mnvx: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/311-citizen-requests-for-service-7ixm-mnvx is just another Postgres schema.