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 measuring_progress_questionnaire_volunteerism table in this repository, by referencing it like:
"edmonton-ca/measuring-progress-questionnaire-volunteerism-js4g-y89z:latest"."measuring_progress_questionnaire_volunteerism"or in a full query, like:
SELECT
":id", -- Socrata column ID
"fsa", -- Forward Sortation Area (first 3 characters of postal code)
"coe_work", -- Profiling question. Question: Do you work for the City of Edmonton? || Possible Answers: Yes|No
"age", -- Profiling question. Question: Your age? || Possible Answers: 15 - 18|18 - 24|25 - 34|35 - 44|45 - 54|55 - 64|65 years and over|Refused
"job_status", -- Profiling question. Question: Which of the following best describes your employment status, are you currently... || Possible Answers: Working full time|Working part time|A student|Not working outside the home|Retired|Prefer not to answer
"q15_volunteeringatyourlocallibraryorothercommunityfacility", -- Question: Have you volunteered for... - your local library or other community facility || Possible Answers: 1 - Selected | 0 - Not selected
"household_income", -- Profiling question. Question: Which of the following best describes your total annual household income before taxes? || Possible Answers: Less than $20,000|Between $20,000 and $29,999|Between $30,000 and $49,999|Between $50,000 and $79,999|Between $80,000 and $119,999|$120,000 or more|Prefer not to answer
"completiondate", -- Date/Time the respondent finished the survey.
"q12", -- Question: Over the past year, have you volunteered with or for a community group, charity or similar organization?? || Possible Answers: Yes|No|Don't Remember
"devicetype", -- System Captured, Device used by the respondent. Question: Device Type? - DeviceType || Possible Answers: Tablet/Desktop/Phone
"qdr", -- Profiling question. Question: City Quadrant? || Possible Answers: NW|NE|SE|SW
"q15_volunteeringwithanorganizationinvolvedwithyouthchildren", -- Question: Have you volunteered for... - an organization involved with youth/children || Possible Answers: 1 - Selected | 0 - Not selected
"q15_volunteeringforareligiousgroup", -- Question: Have you volunteered for... - a religious group || Possible Answers: 1 - Selected | 0 - Not selected
"q15_volunteeringforanenvironmentalorganization", -- Question: Have you volunteered for... - an environmental organization || Possible Answers: 1 - Selected | 0 - Not selected
"q15_donatingtimetoalocalcharity", -- Question: Have you volunteered for... - Donating time to a local charity || Possible Answers: 1 - Selected | 0 - Not selected
"browsertype", -- System Captured, Browser used by the respondent. Question: Browser Type? - BrowserType || Possible Answers: Internet Explorer/Firefox/Safari/Google Chrome/Opera/Android/BlackBerry/Unknown
"vote", -- Profiling question. Question: Did you vote in the most recent municipal election for the City of Edmonton? || Possible Answers: Yes|No|I was not eligible
"residence", -- Profiling question. Question: What type of residence do you live in? || Possible Answers: House|Duplex|Four-plex|Apartment|Condo|Townhouse|Other
"own_rent", -- Profiling question. Question: Do you currently own or rent your place of residence? || Possible Answers: Own|Rent
"born_in_canada", -- Profiling question. Question: Were you? || Possible Answers: Born in Canada|Moved to Canada from somewhere else
"education", -- Profiling question. Question: What is the highest level of education you have achieved?? || Possible Answers: Less than high school|Graduated high school|Graduated college, technical or vocational school|Graduated university|Prefer not to answer
"q15_volunteeringforanycommunityboardorcommitteeotherthanaci", -- Question: Have you volunteered for... - any community board or committee other than a City one || Possible Answers: 1 - Selected | 0 - Not selected
"children", -- Question: Children in your household? || Possible Answers: Yes|No
"personal_income", -- Profiling question. Question: Which of the following best describes your total personal annual income before taxes? || Possible Answers: Less than $20,000|Between $20,000 and $29,999|Between $30,000 and $49,999|Between $50,000 and $79,999|Between $80,000 and $119,999|$120,000 or more|Prefer not to answer
"number_in_household", -- Question: How many people are there in your household?
"language", -- Profiling question. Question: What is the primary language spoken in your household? || Possible Answers: English|French|Other
"q15_noneofthese", -- Question: Have you volunteered for... - None of these || Possible Answers: 1 - Selected | 0 - Not selected
"responsedate", -- Date/Time the respondent first opened/started the survey.
"q15_other", -- Question: Have you volunteered for... - Other || Possible Answers: 1 - Selected | 0 - Not selected
"gender", -- Profiling question. Question: Your gender? || Possible Answers: Female|Male|Other|I prefer not to answer
"q15_volunteeringatcommunityeventssuchasfestivalscityeventso", -- Question: Have you volunteered for... - community events such as festivals || Possible Answers: 1 - Selected | 0 - Not selected
"q15_volunteeringforacityofedmontonboardorcommittee", -- Question: Have you volunteered for... - a City of Edmonton board or committee || Possible Answers: 1 - Selected | 0 - Not selected
"q15_volunteeredforacommunitysafetyprojectorprogram" -- Question: Have you volunteered for... - a community safety project or program || Possible Answers: 1 - Selected | 0 - Not selected
FROM
"edmonton-ca/measuring-progress-questionnaire-volunteerism-js4g-y89z:latest"."measuring_progress_questionnaire_volunteerism"
LIMIT 100;Connecting to the DDN is easy. All you need is an existing SQL client that can connect to Postgres. As long as you have a SQL client ready, you'll be able to query edmonton-ca/measuring-progress-questionnaire-volunteerism-js4g-y89z with SQL in under 60 seconds.
Query Your Local Engine
bash -c "$(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 edmonton-ca/measuring-progress-questionnaire-volunteerism-js4g-y89z: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 edmonton-ca/measuring-progress-questionnaire-volunteerism-js4g-y89zCheckout 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 edmonton-ca/measuring-progress-questionnaire-volunteerism-js4g-y89z:latestThis will download all the objects for the latest tag of edmonton-ca/measuring-progress-questionnaire-volunteerism-js4g-y89z 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 edmonton-ca/measuring-progress-questionnaire-volunteerism-js4g-y89z: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 edmonton-ca/measuring-progress-questionnaire-volunteerism-js4g-y89z: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, edmonton-ca/measuring-progress-questionnaire-volunteerism-js4g-y89z is just another Postgres schema.