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 feed_the_future_tajikistan_zone_of_influence table in this repository, by referencing it like:
"usaid-gov/feed-the-future-tajikistan-zone-of-influence-22zc-pnbc:latest"."feed_the_future_tajikistan_zone_of_influence"or in a full query, like:
SELECT
":id", -- Socrata column ID
"c04", -- What is NAME s age? (in years)
"othvitagrp",
"a06", -- Type of household:
"a21",
"d09", -- What is the main source of water for purposes of bathing, washing, cooking, kitchen garden, etc.?
"modd_missing",
"h16", -- Potatoes or any other foods made from roots
"id_code", -- Respondent ID in the household
"bmi", -- Women s BMI (weight in kg (height in m squared))
"h03", -- Please tell me how old you are. What was your age at your last birthday?
"urbrur", -- Urban, rural
"d04", -- How many rooms are there in this dwelling?
"d11", -- What is the secondary source of cooking fuel for your household?
"zic_school_cur",
"h02_year", -- In what month and year were you born?
"modf_missing",
"h06", -- Are you currently pregnant?
"h18", -- NOT COLLECTED IN THIS SURVEY
"h08", -- Height in centimeters:
"country", -- Country recorded in module A
"zic_edu_lvl",
"a05", -- Sex of respondent:
"zih_age_check_yn",
"f03", -- In the past 4 weeks 30 days did you or any household member go to sleep at night hungry because there was not enough food?
"h24x", -- NOT COLLECTED IN THIS SURVEY
"eggsgrp", -- Eggs
"a02", -- Cluster number
"underwght", -- Underweight (BMI 18.5)
"h15", -- Pumpkin, carrots, squash that are yellow or orange inside or other local yellow orange foods
"c02", -- What is NAME s sex?
"h25", -- Cheese, yogurt, or other milk products
"d07", -- What is the main source of electricity?
"zih_anemia_consent",
"foodsum", -- Number of Food Groups Consumed 0-9
"zic_school_ever",
"h23", -- Fresh or dried fish, any other seafood
"f01", -- In the past 4 weeks 30 days was there ever no food to eat of any kind in your house because of lack of resources to get food?
"a09",
"zih_anemia_test_result",
"h17", -- Any dark green leafy vegetables such as cabbage, lettuce
"d06", -- What is the main source of drinking water for your household?
"f02", -- How often did this happen in the past 4 weeks 30 days ?
"h14", -- Food made from grains, such as bread, rice, noodles, porridge, or other grain food
"d01", -- Roof top material (outer covering):
"beansgrp", -- Legumes and nuts
"c03", -- What is NAME s relationship to the primary respondent?
"milkgrp", -- Dairy products (milk, yogurt, cheese)
"h20", -- Liver, kidney, heart, or other organ meats
"h29", -- NOT COLLECTED IN THIS SURVEY
"h28", -- Condiments for flavor, such as chilies, spices, herbs, or fish powder
"zih_bmi",
"pbs_id",
"h30", -- NOT COLLECTED IN THIS SURVEY
"d03", -- Exterior Walls
"d10", -- What is the secondary source of electricity?
"d02", -- Floor material
"f04", -- How often did this happen in the past 4 weeks 30 days ?
"f05", -- In the past 4 weeks 30 days did you or any household member go a whole day and night without eating anything at all because there was not enough food?
"h07", -- Weight in kilograms:
"d08", -- What is the main source of cooking fuel for your household?
"grainsgrp", -- Grains, roots and tubers
"f06", -- How often did this happen in the past 4 weeks 30 days ?
"h02_month", -- In what month and year were you born?
"zih_women_age_range",
"othfrtgrp", -- Other fruits and vegetables
"wmwght", -- Women s sample weight
"lfygrngrp", -- Other Vitamin A rich vegetables and fruits
"h22", -- Eggs
"h19", -- Any other fruits or vegetables
"zih_married",
"zic_literacy",
"h24", -- Any foods made from beans, peas, lentils, nuts, or seeds
"fleshgrp", -- Flesh foods (meat, fish, poultry and liver organ meats)
"hhwght", -- Derived variable, household weight
"h27", -- Any sugary foods such as chocolates, sweets, candies, pastries, cakes, or biscuits
"h21", -- Any meat, such as beef, pork, lamb, goat, chicken, or duck
"d05", -- What is the main type of toilets your household uses?
"organgrp", -- Organ meat
"h26" -- Any oil, fats, or butter, or foods made with any of these
FROM
"usaid-gov/feed-the-future-tajikistan-zone-of-influence-22zc-pnbc:latest"."feed_the_future_tajikistan_zone_of_influence"
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 usaid-gov/feed-the-future-tajikistan-zone-of-influence-22zc-pnbc with SQL in under 60 seconds.
This repository is an "external" repository. That means it's hosted elsewhere, in this case at data.usaid.gov. When you queryusaid-gov/feed-the-future-tajikistan-zone-of-influence-22zc-pnbc:latest on the DDN, we "mount" the repository using the socrata mount handler. The mount handler proxies your SQL query to the upstream data source, translating it from SQL to the relevant language (in this case SoQL).
We also cache query responses on the DDN, but we run the DDN on multiple nodes so a CACHE_HIT is only guaranteed for subsequent queries that land on the same node.
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 (like this repository), 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, where the author has pushed Splitgraph Images to the repository, you can "clone" and/or "checkout" the data using sgr cloneand sgr checkout.
Mounting Data
This repository is an external repository. It's not hosted by Splitgraph. It is hosted by data.usaid.gov, and Splitgraph indexes it. This means it is not an actual Splitgraph image, so you cannot use sgr clone to get the data. Instead, you can use the socrata adapter with the sgr mount command. Then, if you want, you can import the data and turn it into a Splitgraph image that others can clone.
First, install Splitgraph if you haven't already.
Mount the table with sgr mount
sgr mount socrata \
"usaid-gov/feed-the-future-tajikistan-zone-of-influence-22zc-pnbc" \
--handler-options '{
"domain": "data.usaid.gov",
"tables": {
"feed_the_future_tajikistan_zone_of_influence": "22zc-pnbc"
}
}'That's it! Now you can query the data in the mounted table like any other Postgres table.
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, usaid-gov/feed-the-future-tajikistan-zone-of-influence-22zc-pnbc is just another Postgres schema.