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 animal_field_data_fiscal_year_2022_2023 table in this repository, by referencing it like:
"dallasopendata/animal-field-data-fiscal-year-2022-2023-c7pr-ajef:latest"."animal_field_data_fiscal_year_2022_2023"or in a full query, like:
SELECT
":id", -- Socrata column ID
"user_id", -- Unique ID number assigned to the staff person who entered the record.
"dispatch_date", -- Date and time activity was dispatched.
"created_date_time", -- Date and time a record was created.
"cancel_reason", -- Reason an activity was cancelled.
"activity_status", -- Status used to track progress of activity.
"activity_comment", -- Additional staff notes.
"activity_quantity_3", -- Count of the respective result field (Activity Result 3)
"animal_description", -- Field in which DAS Staff can enter notes related to the appearance of the animal involved in a service request or activity.
"final_activity_result", -- Notes for work completed
"animal_type", -- Animal category: dog, cat, wildlife, other, etc.
"street_name", -- Street on which the activity or service request occurred.
"street_direction", -- Direction of the street on which the activity or service request occurred.
"street_number", -- House, apartment, or building number at which the activity or service request occurred.
"street_address", -- Full address of the location in which the activity or service request occurred.
"activity_subtype", -- Sub-category that further narrows the purpose of the activity or service request.
"working_date", -- Date and time officer started working on the assigned activity
"call_date_time", -- Date and time a call was received.
"activity_result_5", -- Notes for work completed
"activity_result_2", -- Notes for work completed
"activity_result_1", -- Notes for work completed
"activity_quantity_1", -- Count of the respective result field (Activity Result 1)
"council_district", -- Unique area mapped out by the City of Dallas that is represented by a specific City Council Office and Member.
"zip_code", -- The five digit zip code in which an activity or service request occurred.
"activity_number", -- Unique number assigned to an activity related to a service request.
"activity_quantity_5", -- Count of the respective result field (Activity Result 5)
"tag_number", -- Unique number assigned to a microchip implanted in an animal for identification.
"officer_id", -- Unique number assigned to every Animal Service Officer in Database.
"activity_sequence", -- Sequence starts with 1 usually then a follow up sequence is created until activity is completed.
"census_tract", -- Unique area mapped out by the federal government for purposes of the census.
"final_citation_quantity", -- Count of the citations for Activity or SR Number
"mapsco", -- Unique code used in GIS mapping to more accurately identify a location.
"complete_date", -- Date the activity was completed.
"final_activity_quantity", -- Count of the respective result field (Final Activity Result)
"activity_result_4", -- Notes for work completed
"activity_quantity_4", -- Count of the respective result field (Activity Result 4)
"apartment", -- The unit number at the address where a service request or activity occurred.
"city", -- The city in which an activity or service request occurred.
"activity_type", -- Category that identifies the purpose of the activity or service request.
"month", -- Month the record was created.
"activity_result_3", -- Notes for work completed
"animal_intake_id", -- Unique number assigned to each animal when their record is created in the database.
"service_request_number", -- Unique number assigned to a service request by Salesforce when it is submitted by a resident through 3-1-1.
"activity_quantity_2", -- Count of the respective result field (Activity Result 2)
"street_type", -- Identifies the kind of street on which the activity or service request occurred (ex. Drive or avenue).
"animal_count", -- Number of animals involved in a specific activity or service request.
"year", -- City of Dallas Fiscal Year the record was created.
"activity_priority", -- Priority assigned to the activity or service request based on pre-determined guidelines reflecting the urgency of the matter.
"state" -- The state in which an activity or service request occurred.
FROM
"dallasopendata/animal-field-data-fiscal-year-2022-2023-c7pr-ajef:latest"."animal_field_data_fiscal_year_2022_2023"
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 dallasopendata/animal-field-data-fiscal-year-2022-2023-c7pr-ajef with SQL in under 60 seconds.
This repository is an "external" repository. That means it's hosted elsewhere, in this case at www.dallasopendata.com. When you querydallasopendata/animal-field-data-fiscal-year-2022-2023-c7pr-ajef: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 www.dallasopendata.com, 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 \
"dallasopendata/animal-field-data-fiscal-year-2022-2023-c7pr-ajef" \
--handler-options '{
"domain": "www.dallasopendata.com",
"tables": {
"animal_field_data_fiscal_year_2022_2023": "c7pr-ajef"
}
}'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, dallasopendata/animal-field-data-fiscal-year-2022-2023-c7pr-ajef is just another Postgres schema.