Query the Data Delivery Network

Query the DDN

The 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 and query any version of over 40,000 datasets that are hosted or proxied by Splitgraph.

For example, you can query the dob_now_build_elevator_permit_applications table in this repository, by referencing it like:


or in a full query, like:

    ":id", -- Socrata column ID
    "incomplete_date", -- Incomplete Date
    "gl_company", -- Name of the company providing General Liability insurance to the applicant's firm
    "worker_compensation_company", -- Name of the company providing Workers Compensation insurance to the applicant's firm
    "applicant_license_number", -- Applicant's license number, DOB issues licenses  to qualified individuals working in the construction trades in New York City.
    "job_filing_number", -- A unique identifier assigned to a job filing. It consists of job number (a letter indicating the borough followed by an 8-digit number)  hyphenated with Filing Number (a 2-digit code identifying the filing type). Once the permit is issued, a suffix  "-VT" is added to the job filing number. (Example: B00016701-I1-VT)
    "owner_type", -- Owner Type
    "applicant_state", -- State of the applicant's firm
    "amount_due", -- Balance remaining 
    "disability_company", -- Insurance Information Disability
    "owner_firstname", -- First Name of Owner
    "first_objection_date", -- First Objection Date
    "zip", -- Zip code of the job location
    "is_in_conjunction", -- Flag: Yes or No
    "designprofessional_firstname", -- First Name of Design Professional
    "applicant_businessname", -- Name of Applicant Business
    "applicant_firstname", -- First name of the applicant
    "resubmission_date", -- Re-submission Date
    "street_name", -- The Street Name of the job location
    "worker_compensation_policy", -- Policy number of the Workers Compensation insurance covering the applicant's firm
    "worker_compensation", -- Expiration date of the Workers Compensation  insurance policy covering the applicant's firm
    "owner_city", -- City of the Owner
    "amount_paid", -- Amount paid by applicant
    "no_good_check", -- A fee required if first check payment to DOB was rejected / returned
    "descriptionofwork", -- Scope of Work
    "owner_state", -- State of the Owner
    "gl_expirationdate", -- Expiration date of the General Liability insurance policy covering the applicant's firm
    "house_number", -- The house number of the job location
    "lot", -- Tax lot number of the job location. Assigned by the Department of Finance.
    "designprofessional", -- Design Professional Business Name
    "filing_type", -- Indicates whether this filing is new, subsequent or Post Approval Amendment (PAA) filing
    "filing_status", -- Indicates status of the permit application. Example: Permit Issued
    "asbestosabatementcompliance", -- Asbestos Abatement Compliance
    "gl_policy", -- Policy number of the General Liability insurance covering the applicant's firm
    "disability_policy", -- Insurance Information Disability Certification/Policy No
    "filing_date", -- Filing Date; Date and Time Format: '2018-04-25 21:52:00.000'
    "bin", -- Building Identification Number (BIN) of the job location. Assigned by Department of City Planning.
    "buildingstories", -- Number of Stories in the Building 
    "total_fee", -- Indicates total fee amount (quantity * cost)
    "applicant_zip", -- ZIP code of the applicant's firm
    "depacp5controlno", -- DEP ACP-5 Control No.
    "electrical_permit_number", -- Electrical Permit Number
    "block", -- Tax block number of the job location. Assigned by the Department of Finance.
    "designprofessional_zip", -- Zip code of Design Professional's State
    "filingstatus_or_filingincludes", -- Indicates if the filing status includes any other filings
    "associatedjobnumber", -- Associated BIS Job Number if applicable; 
    "designprofessional_city", -- City of Design Professional's firm
    "owner_businessname", -- Owner Information Business Name
    "disability_expirationdate", -- Insurance Information Disability Expiration Date
    "owner_zip", -- Zip of the Owner
    "elevatordevicetype", -- Expected Values: Accessibility Lift, Conveyor,  Dumbwaiter, Elevator, Escalator, Moving Walk, Personnel Hoist
    "filing_number", -- A 2-digit code identifying the filing type
    "filing_fee", -- Fee required for the job filing
    "building_code", -- Building code which is single select value
    "estimated_cost", -- Estimated Cost
    "applicant_city", -- City of the applicant's firm
    "designprofessional_state", -- State of Design Professional's State
    "building_type", -- Category of Building - used for Inconjunction fee. 1,2,3 family - 130$ or other - 225$
    "owner_address", -- Street Address of the Owner
    "designprofessional_license", -- Design Professional License number, DOB issues licenses  to qualified design professionals working in the construction trades in New York City.
    "owner_title", -- Title information for Owner
    "owner_lastname", -- Last Name of Owner
    "designprofessional_lastname", -- Last Name of Design Professional
    "applicant_address", -- Street address of the applicant's firm
    "applicant_lastname", -- Last name of the applicant
    "signedoff_date", -- Signed Off Date
    "permit_entire_date", -- Permit Entire Date
    "last_objection_date", -- Last Objection date
    "last_incomplete_submission", -- Last Incomplete Submission Date
    "plan_examiner_assigned_date", -- Plan Examiner Assigned Date
    "job_number", -- A 9-digit identifier for the job. The first letter indicates the borough for which the filing is associated, followed by an 8-digit ID number
    "borough", -- Borough of job location
    "designprofessional_address" -- Street address of the Design Professional
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 cityofnewyork-us/dob-now-build-elevator-permit-applications-kfp4-dz4h with SQL in under 60 seconds.

Query Your Local Engine

Install Splitgraph Locally
bash -c "$(curl -sL"

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 cityofnewyork-us/dob-now-build-elevator-permit-applications-kfp4-dz4h: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 cityofnewyork-us/dob-now-build-elevator-permit-applications-kfp4-dz4h

Checkout 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 cityofnewyork-us/dob-now-build-elevator-permit-applications-kfp4-dz4h:latest

This will download all the objects for the latest tag of cityofnewyork-us/dob-now-build-elevator-permit-applications-kfp4-dz4h 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 cityofnewyork-us/dob-now-build-elevator-permit-applications-kfp4-dz4h: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 cityofnewyork-us/dob-now-build-elevator-permit-applications-kfp4-dz4h:latest

This 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, cityofnewyork-us/dob-now-build-elevator-permit-applications-kfp4-dz4h is just another Postgres schema.

Related Documentation: