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 child_and_adult_care_food_programs_cacfp_day_care table in this repository, by referencing it like:
"texas-gov/child-and-adult-care-food-programs-cacfp-day-care-pgyj-5euh:latest"."child_and_adult_care_food_programs_cacfp_day_care"or in a full query, like:
SELECT
":id", -- Socrata column ID
"ceadministratoremail", -- CE administrator email address
":@computed_region_9y59_55ru",
"participatingascacfpcent", -- Contracting Entity (CE) also participates as a sponsor for CACFP centers. Data displayed as: Y/N
"capacity", -- Licensed site capacity
"ifother_pleaseexplain", -- If “other” is indicated, explanation of meal preparation method.
"howaremealsprepared", -- Method used by site to prepare meals. Data displayed as: Prepared on site/Other
"sitecontactsaluation", -- Honorific salutation for site contact. Optional entry. Format: Mr., Ms. Dr., etc.
"sitestreetaddressstate", -- Site street address, state
"cestreetaddressstate", -- Contracting Entity (CE) street address, state
"sitecontactfirstname", -- Site contact first name. Site contact is the person in charge of this center on a daily basis
"sitcontactlastname", -- Site contact last name. Site contact is the person in charge of this center on a daily basis.
"sitecontactemail", -- Site contact email address. Site contact is the person in charge of this center on a daily basis.
"sitecontactphone", -- Site contact phone number. Site contact is the person in charge of this center on a daily basis.
"numberofchildrenenrolled", -- Number of children enrolled in program
"applicationeffectivedate", -- Date Contracting Entity (CE) is approved to begin program participation for program year. New field added 2017-2018.
"geocoded_column", -- Geolocation of site based on site street address for map visualization. Null values in geolocation data is most likely due to a P.O. Box address listed for a site address.
"licenseexpriationdate", -- Date the license or registration expires
"sitemailingaddressline1", -- Site mailing address, line 1
"licenseeffectivedate", -- Date the license or registration takes effect
"license_registrationnumber", -- Site’s license or registration number
"sitemailingaddresszipcode", -- Site mailing address, zip code
"sitemailingaddressstate", -- Site mailing address, state
"sitemailingaddresscity", -- Site mailing address, city
"sitemailingaddressline2", -- Site mailing address, line 2 (if applicable)
"sitestreetaddresszipcode", -- Site street address, zip code
"sitestreetaddresscity", -- Site street address, city
"sitestreetaddressline2", -- Site street address, line 2 (if applicable)
"sitestreetaddressline1", -- Site street address, line 1
"sitecounty", -- County in which the site is located
"sitename", -- Site name
"siteid", -- Number assigned to identify site within CE
"ceadministratorphone", -- CE administrator phone number
"ceadministratortitleposition", -- CE administrator title or position
"ceadministratorlastname", -- CE administrator last name
"ceadministratorfirstname", -- CE administrator first name
"ceadministratorsalutation", -- Honorific salutation for CE administrator. Optional entry for CE. Format: Mr., Ms., Dr., etc.
"cemailingaddresszipcode", -- Contracting Entity (CE) mailing address, zip code
"cemailingaddressstate", -- Contracting Entity (CE) mailing address, state
"cemailingaddresscity", -- Contracting Entity (CE) mailing address, city
"cemailingaddressline2", -- Contracting Entity (CE) mailing address, line 2 (if applicable)
"cemailingaddressline1", -- Contracting Entity (CE) mailing address, line 1
"cestreetaddresszipcode", -- Contracting Entity (CE) street address, zip code
"cestreetaddresscity", -- Contracting Entity (CE) street address, city
"cestreetaddressline2", -- Contracting Entity (CE) street address, line 2 (if applicable)
"cestreetaddressline1", -- Contracting Entity (CE) street address, line 1
"tdaregion", -- Texas Department of Agriculture (TDA) service region
"esc", -- Educational Service Center (ESC) region
"cecounty", -- County in which the Contracting Entity (CE) is located
"countydistrictcode", -- County District Code for county in which Contracting Entity (CE) in located
"typeofagency", -- Type of agency the Contracting Entity (CE) operates as. Data displayed as: Government Agency/Military Installation/Private Non Profit Organization
"cename", -- Contracting Entity (CE) name
"ceid", -- Unique number assigned to Contracting Entity (CE) to identify as program sponsor
"reporttype", -- Type of information being reported in the dataset
"programyear", -- A program year for Child and Adult Care Food Programs (CACFP) is defined as October 1 of one year through September 30 of the following year.
":@computed_region_fd5q_j34z",
":@computed_region_ywmh_rrwq",
":@computed_region_hy99_5a2i",
":@computed_region_346f_s9gh"
FROM
"texas-gov/child-and-adult-care-food-programs-cacfp-day-care-pgyj-5euh:latest"."child_and_adult_care_food_programs_cacfp_day_care"
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 texas-gov/child-and-adult-care-food-programs-cacfp-day-care-pgyj-5euh 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 texas-gov/child-and-adult-care-food-programs-cacfp-day-care-pgyj-5euh: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 texas-gov/child-and-adult-care-food-programs-cacfp-day-care-pgyj-5euhCheckout 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 texas-gov/child-and-adult-care-food-programs-cacfp-day-care-pgyj-5euh:latestThis will download all the objects for the latest tag of texas-gov/child-and-adult-care-food-programs-cacfp-day-care-pgyj-5euh 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 texas-gov/child-and-adult-care-food-programs-cacfp-day-care-pgyj-5euh: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 texas-gov/child-and-adult-care-food-programs-cacfp-day-care-pgyj-5euh: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, texas-gov/child-and-adult-care-food-programs-cacfp-day-care-pgyj-5euh is just another Postgres schema.