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 dsc_permits table in this repository, by referencing it like:
"performance-cityofhenderson/dsc-permits-fpc9-568j:latest"."dsc_permits"or in a full query, like:
SELECT
":id", -- Socrata column ID
"ownername", -- Owner name from the parcel information.
"professionalstatelicnbr", -- The contractor's license number of the professional the permit was issued to.
"parceladdressnumber", -- The address number for the situs of the permit.
"totalconstructioncostpublic", -- An estimate of valuation of public (off-site) construction.
"residentialvalue", -- Valuation of permitted residential space. (USD)
"residentialgaragearea", -- Square footage of garage space permitted in a residence.
"category", -- Classification assigned to the permit for reporting, primarily valuation.
"permitdescription", -- General description of the permit or plan provided by customer.
"permittype", -- Type of permit.
"finalizeddate", -- Date of completion of permit.
"applymonth", -- Month of initial entry into permitting and land management system
"applydate", -- Date (long) of initial entry into permitting and land management system
"permitsquarefootagetotal", -- All permitted square footage (Combined Area + Residential Garage Area + Residential Porch Area + Residential Patio Area)
"workingdaysbetweenapplyd", -- This represents the business days that pass between application and issuance. NOTE: This is total time including review, time between submissions, and time before permits are paid in full for issuance.
"combinedarea", -- The total combined area of the commercial space, multi-family living space, and residential living space.
"parceladdresszip", -- The zip code of the situs of the permit.
"parceladdressstreettype", -- The street type (Rd., Hwy., Dr., etc.) associated to situs of the permit.
"residentiallivingarea", -- Square footage of residential living space permitted. Does not include garage, patio, or similar areas.
"permitstatus", -- Current status of the permit.
"workclass", -- Classification of permit.
"issuedate", -- Issuance date (long) of permit.
"valuationtotal", -- Computed total of valuation including miscellaneous permit types not represented in the Combined Total column.
"professionalname", -- Business name of the professional the permit was issued to.
"gisy", -- The latitude of the geographic center of the parcel permitted.
"commercialvalue", -- Valuation of permitted commercial space. (USD)
"multifamilylivingarea", -- Square footage of multi-family living space permitted.
"professionalphone", -- The phone number of the professional the permit was issued to.
"parcelnumber", -- The parcel (APN) permitted.
"multifamilydwellingunits", -- The number of permitted dwelling spaces constructed within the multi-family permit.
"combinedvalue", -- Commercial Value + Residential Value + Multi-Family Value
"multifamilyvalue", -- Valuation of permitted multi-family space. (USD)
"residentialpatioarea", -- Square footage of patio space permitted in a residence.
"expiredate", -- Date of expiration of permit. Subject to change until permit completion based on administrative code.
"applydateqtr", -- The quarter (numeric) of the permit's initial entry into permitting and land management system
"applydatefy", -- Fiscal Year of initial entry into permitting and land management system
"professionaladdress", -- The address of the professional the permit was issued to.
"parceladdresspredirection", -- The street direction for the situs of the permit.
"locationdescription", -- Description of the permitted area including a more detailed location, scope, and overview.
"parceladdressstreet", -- The street name of the situs of the permit.
"totalconstructioncostprivate", -- An estimate of valuation of private (on-site) construction .
"gisx", -- The longitude of the geographic center of the parcel permitted.
"department", -- Represents the Department or Division that the permit's primary classification fits into.
"permitnumber", -- Unique identified number assigned to the permit.
"owneraddress", -- Owner address from the parcel information.
"parceladdressstate", -- The state of the situs of the permit.
"residentialdwellingunits", -- The number of permitted dwelling spaces constructed within the residential permit.
"submittalmethod", -- Method of application from the customer.
"gis_point", -- The combined GIS XY coordinates (geocoded) for mapping.
"residentialporcharea", -- Square footage of porch space permitted in a residence.
"commercialbuildingarea", -- Square footage of commercial space permitted.
"parceladdresscity" -- The city of the situs of the permit.
FROM
"performance-cityofhenderson/dsc-permits-fpc9-568j:latest"."dsc_permits"
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 performance-cityofhenderson/dsc-permits-fpc9-568j 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 performance-cityofhenderson/dsc-permits-fpc9-568j: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 performance-cityofhenderson/dsc-permits-fpc9-568jCheckout 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 performance-cityofhenderson/dsc-permits-fpc9-568j:latestThis will download all the objects for the latest tag of performance-cityofhenderson/dsc-permits-fpc9-568j 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 performance-cityofhenderson/dsc-permits-fpc9-568j: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 performance-cityofhenderson/dsc-permits-fpc9-568j: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, performance-cityofhenderson/dsc-permits-fpc9-568j is just another Postgres schema.