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 weekly_fort_collins_opendata_portal_analytics table in this repository, by referencing it like:
"opendata-fcgov/weekly-fort-collins-opendata-portal-analytics-it47-5a8q:latest"."weekly_fort_collins_opendata_portal_analytics"or in a full query, like:
SELECT
":id", -- Socrata column ID
"meta_row_index", -- Metadata field for a suggested sort order. Sort this column in ascending order to order the dataset the way it was intended from the source system.
"ga_sessions", -- From Google Analytics API: the total number of sessions
"ga_bounces", -- From Google Analytics API: the total number of single page (or single interaction hit) sessions for the property
"assettitle", -- The title of the data asset, when a single asset is referenced in the URL
"enddate", -- Inclusive end date for analytics capture
"ga_avgsessionduration", -- From Google Analytics API: the average duration (in seconds) of users sessions
"ga_hits", -- From Google Analytics API: total number of hits for the view (profile). This metric sums all hit types, including pageview, custom event, ecommerce, and other types. Because this metric is based on the view (profile), not on the property, it is not the same as the propertys hit volume
"ga_avgtimeonpage", -- From Google Analytics API: the average time users spent viewing this page or a set of pages
"ga_percentnewsessions", -- From Google Analytics API: the percentage of sessions by users who had never visited the property before
"ga_users", -- From Google Analytics API: the total number of users for the requested time period
"ga_bouncerate", -- From Google Analytics API: the percentage of single-page session (i.e., session in which the person left the property from the first page)
"meta_row_id", -- Metadata field for record hash. This field is a SHA-1 hash of all other fields in the record, used for validation of record uniqueness.
"ga_pageviewspersession", -- From Google Analytics API: the average number of pages viewed during a session, including repeated views of a single page
"url", -- URL of a specific page, or all for all pages in the domain
"ga_pageviews", -- From Google Analytics API: the total number of pageviews for the property
"startdate", -- Inclusive start date for analytics capture
"ga_timeonpage", -- From Google Analytics API: time (in seconds) users spent on a particular page, calculated by subtracting the initial view time for a particular page from the initial view time for a subsequent page. This metric does not apply to exit pages of the property
"ga_newusers", -- From Google Analytics API: the number of sessions marked as a user's first session. This resets each time period
"ga_sessionduration" -- From Google Analytics API: total duration (in seconds) of users sessions
FROM
"opendata-fcgov/weekly-fort-collins-opendata-portal-analytics-it47-5a8q:latest"."weekly_fort_collins_opendata_portal_analytics"
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 opendata-fcgov/weekly-fort-collins-opendata-portal-analytics-it47-5a8q 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 opendata-fcgov/weekly-fort-collins-opendata-portal-analytics-it47-5a8q: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 opendata-fcgov/weekly-fort-collins-opendata-portal-analytics-it47-5a8qCheckout 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 opendata-fcgov/weekly-fort-collins-opendata-portal-analytics-it47-5a8q:latestThis will download all the objects for the latest tag of opendata-fcgov/weekly-fort-collins-opendata-portal-analytics-it47-5a8q 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 opendata-fcgov/weekly-fort-collins-opendata-portal-analytics-it47-5a8q: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 opendata-fcgov/weekly-fort-collins-opendata-portal-analytics-it47-5a8q: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, opendata-fcgov/weekly-fort-collins-opendata-portal-analytics-it47-5a8q is just another Postgres schema.