Vega Transform to Query OmniSciDB

Data transform to load data from an OmniSciDB database in Vega.

This package extends Vega's set of data transforms to support loading data from a database in Vega version 5.0 and higher.

Try this transform in our Observable demo or the scalable Vega demo app.

Usage Instructions

Install the transform with

yarn add vega-transform-omnici-core

To use the core transform, you must set the session. To create a session, create a connection and connect to it. Then assign the session to the Core transform with QueryCore.sesssion(session). the register the transform as querycore.

QueryCore.session(session);
transforms["querycore"] = QueryCore;

Here is a complete example.

import "@mapd/connector/dist/browser-connector";
import QueryCore from "vega-transform-omnisci-core";
import vega from "vega";

const connection = new window.MapdCon()
  .protocol("https")
  .host("metis.mapd.com")
  .port("443")
  .dbName("mapd")
  .user("mapd")
  .password("HyperInteractive");

// connect to core database and create a transform with a handle to the session
connection.connectAsync().then(session => {
  // pass the session to the core transform
  QueryCore.session(session);

  // register OmniSci Core transform
  vega.transforms["querycore"] = QueryCore;

  // now you can use the transform in a Vega spec
  const view = new vega.View(vega.parse(spec))
    .initialize(document.querySelector("#vis"));
  
  view.runAsync();
});

Vega Specifications

Once vega-transform-omnisci-core has been imported and registered, Vega specs can reference the transform and get data from OmniSciDB like this:

{
  "data": [
    {
      "name": "table",
      "transform": [{
        "type": "querycore",
        "query": "select count(*) from flights_donotmodify"
      }]
    }
  ]
}

Check out a complete demo at https://github.com/vega/scalable-vega.