2018 – TechnocratSid Blogs

Sort strings alphabetically rather than lexicographically in Elasticsearch?

technocratsidDecember 3, 2018December 3, 2018

Let's say we have a text field "name" in an elasticsearch index with the following values: Siddhant, SIDTECHNOCRAT, and sid. Now follow the conventions mentioned in String Sorting in Elasticsearch, which talks about using...

Elasticsearch

How to create an Elasticsearch 6.4.1 Plugin

technocratsidOctober 28, 2018October 28, 2018

A plugin provides a way to extend or enhance the basic functionality of Elasticsearch without having to fork it from GitHub. Elasticsearch supports a plugin framework which provides many custom...

Elasticsearch

String sorting in Elasticsearch

technocratsidOctober 22, 2018October 22, 2018

We should not sort on analyzed text field instead we should sort on not_analyzed text field. Let's understand this with an example: Index some documents with a text field "name"....

Elasticsearch Open Source Projects

Elasticsearch plugin for Sentiment Analysis

technocratsidOctober 17, 2018January 5, 2019

I have created an Elasticsearch plugin for sentiment-analysis using Stanford CoreNLP libraries. The plugin is compatible with Elasticsearch 6.4.1. Follow the below steps to use this plugin with your elasticsearch...

Java JavaScript

What is Type Safety ?

technocratsidOctober 15, 2018October 15, 2018

Definition Type safety is prevention of typed errors in a programming language. A type error occurs when someone attempts to perform an operation on a value that doesn’t support that operation. In simple...

Java

Example of Java 8 Streams groupingBy feature

technocratsidOctober 13, 2018October 13, 2018

Statement: Let's say you have a list of integers which you want to group into even and odd numbers. Create a list of integers with four values 1,2,3 and 4: List<Integer>...

Elasticsearch

Usage of Index Alias in Elasticsearch

technocratsidOctober 12, 2018

An index alias is another name for an index or group of indices. It can substitute the original index name in any API. Using index alias you can: Create “views” on a...

Elasticsearch

Elasticsearch 6.x Analyzers

technocratsidOctober 11, 2018October 11, 2018

Elasticsearch Analyzer is a wrapper which wraps three functions: Character filter: Mainly used to strip off some unused characters or change some characters. Tokenizer: Breaks a text into individual tokens(or words) based on...

Elasticsearch

Why ES 6.x doesn’t allow multiple types?

technocratsidOctober 11, 2018November 2, 2018

Before Elasticsearch6.x, the analogy wrt Relational Databases was: Relational DB ⇒ Databases ⇒ Tables ⇒ Rows ⇒ Columns Elasticsearch ⇒ Indices ⇒ Types ⇒ Documents ⇒ Fields which led to...

Elasticsearch

How to re-index an index in Elasticsearch using Java ?

technocratsidOctober 11, 2018November 2, 2018

To re-index an index using java, build a re-index request using ReindexRequestBuilder API like: ReindexRequestBuilder reindexRequest = new ReindexRequestBuilder(client,ReindexAction.INSTANCE) .source("source_index") .destination("destination_index") .refresh(true); After creating a request execute the request: reindexRequest.execute();...