SQL

Elasticsearch SQL is an X-Pack component that allows SQL-like queries to be executed in real-time against Elasticsearch. Whether using the REST interface, command-line or JDBC, any client can use SQL to search and aggregate data natively inside Elasticsearch. One can think of Elasticsearch SQL as a translator, one that understands both SQL and Elasticsearch and makes it easy to read and process data in real-time, at scale by leveraging Elasticsearch capabilities.

In the following example we will search all the documents that has the field house equals to stark, log the result with the tabular view and then manipulate the result to obtain an object easy to navigate.

'use strict'

const { Client } = require('@elastic/elasticsearch')
const client = new Client({ node: 'http://localhost:9200' })

async function run () {
  await client.index({
    index: 'game-of-thrones',
    body: {
      character: 'Ned Stark',
      quote: 'Winter is coming.',
      house: 'stark'
    }
  })

  await client.index({
    index: 'game-of-thrones',
    body: {
      character: 'Arya Stark',
      quote: 'A girl is Arya Stark of Winterfell. And I\'m going home.',
      house: 'stark'
    }
  })

  await client.index({
    index: 'game-of-thrones',
    refresh: true,
    body: {
      character: 'Tyrion Lannister',
      quote: 'A Lannister always pays his debts.',
      house: 'lannister'
    }
  })

  const { body } = await client.sql.query({
    body: {
      query: "SELECT * FROM \"game-of-thrones\" WHERE house='stark'"
    }
  })

  console.log(body)

  const data = body.rows.map(row => {
    const obj = {}
    for (let i = 0; i < row.length; i++) {
      obj[body.columns[i].name] = row[i]
    }
    return obj
  })

  console.log(data)
}

run().catch(console.log)

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