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 ndice_de_informacin_clasificada_y_reservada_del table in this repository, by referencing it like:
"datos-gov-co/ndice-de-informacin-clasificada-y-reservada-del-qckz-5tg9:latest"."ndice_de_informacin_clasificada_y_reservada_del"or in a full query, like:
SELECT
":id", -- Socrata column ID
"formato",
"nombre_del_responsable_de", -- Corresponde al nombre del Área, dependencia, o unidad interna, o al nombre de la entidad externa que creo la información
"medio_de_conservaci_n_y_o", -- Físico Electrónico Físico/Electrónico
"objetivo_leg_timo_de_la", -- Pública: Información que se genere, obtenga, adquiera; o controle en controle. Ej.: Resoluciones Clasificada: Información bajo custodia que requiere solicitud de acceso. Art. 6 Ley 1712. Ej.: Historia Laboral. Reservada: Información exceptuada por daño a intereses públicos. Ej.: Declaración de bienes y rentas
"nombre_o_t_tulo_de_la", -- Palabra o frase con que se da a conocer el nombre o asunto de la información
"subcategor_as",
"nombre_del_responsable_de_1", -- Corresponde al nombre del Área, dependencia o unidad encargada de LA CUSTODIA O CONTROL DE LA INFORMACION para efecto de permitir acceso
"nombre_o_t_tulo_de_la_categor", -- Término con el que se da a conocer el nombre o asunto de la información
"fundamento_constitucional", -- Norma, artículo, inciso o parágrafo.
"fundamento_jur_dico_de_la", -- Mención de la norma jurídica que sirve como fundamento jurídico para la clasificación o reserva de la información.
"plazo_de_clasificaci_n_o", -- Tiempo que cobija la clasificación o reserva en años en número ej: 1 = un año 0.5 = medio año
"excepci_n_total_o_parcial", -- Según sea integral o parcial la clasificación, las partes o s
"idioma", -- Idioma, lengua o dialecto en que se encuentra el activo
"fecha_de_la_calificaci_n",
"calificaci_n",
"fecha_de_generaci_n_de_la"
FROM
"datos-gov-co/ndice-de-informacin-clasificada-y-reservada-del-qckz-5tg9:latest"."ndice_de_informacin_clasificada_y_reservada_del"
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 datos-gov-co/ndice-de-informacin-clasificada-y-reservada-del-qckz-5tg9 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 datos-gov-co/ndice-de-informacin-clasificada-y-reservada-del-qckz-5tg9: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 datos-gov-co/ndice-de-informacin-clasificada-y-reservada-del-qckz-5tg9Checkout 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 datos-gov-co/ndice-de-informacin-clasificada-y-reservada-del-qckz-5tg9:latestThis will download all the objects for the latest tag of datos-gov-co/ndice-de-informacin-clasificada-y-reservada-del-qckz-5tg9 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 datos-gov-co/ndice-de-informacin-clasificada-y-reservada-del-qckz-5tg9: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 datos-gov-co/ndice-de-informacin-clasificada-y-reservada-del-qckz-5tg9: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, datos-gov-co/ndice-de-informacin-clasificada-y-reservada-del-qckz-5tg9 is just another Postgres schema.