Google Indexing

Submitted By:Mohd. Tahoor Shamsi

What is Google Indexing? Indexing is the process of creating indexes for record collections.

Google index is the place where all the data the Google has collected is stored.

Google Indexing is process of a Google collecting, parses and stores data for use by Google.

Contd… The purpose of storing a index is to optimise speed and performance in finding relevant documents for a search query.

Without the index Google would scan every document in the corpus, which would require considerable time and computing power.

Google Indexing Process

Index Design FactorsMajor factors in designing a search engine's architecture include:

Merge Factors : How data enters the index, or how words or subject features are added to the index during text corpus traversal, and whether multiple indexers can work asynchronously. The indexer must first check whether it is updating old content or adding new content. Traversal typically correlates to the data collection policy. Search engine index merging is similar in concept to the SQL Merge command and other merge algorithms

Contd… Storage Techniques: How to store the index data, that is, whether information should be data compressed or filtered.

Index size: How much computer storage is required to support the index.

Lookup speed How quickly a word can be found in the Inverted index. The speed of finding an entry in a data structure, compared with how quickly it can be updated or removed, is a central focus of computer science.

Contd… Maintenance: How the index is maintained over time.

Fault tolerance How important it is for the service to be reliable. Issues include dealing with index corruption, determining whether bad data can be treated in isolation, dealing with bad hardware, partitioning, and schemes such as hash based or composite partitioning,

 as well as replication.

Web Search Engine A web search engine is a software system that is designed to search for information on the World Wide.

These pages are retrieved by a web crawler An automated web browser which follows every link it sees.

Another program, called an indexer, then reads these documents and creates an Index based on the words contained in each document.

The contents of each page are then analyzed to determine how it should be indexed.

Contd… Each search engine uses a proprietary algorithm to create its indices such that, ideally, only meaningful results are returned for each Query.

How Indexing Works?A User enters a query in to a search engine, the Engine examines its index and provides a listing of best matching web pages according to criteria, Usually with a short summary containing the Document’s title.

Google Search Syntax Google’s advanced search web form gives several additional fields which may used to qualify searches by search criteria as date of first retrieval.

All advanced queries transform to regular queries, usually with additional qualified term.

Google's search engine normally accepts queries as a simple text, and breaks up the user's text into a sequence of search terms, which will usually be words that are to occur in the results, but one can also use Boolean operators, such as: quotations marks (") for a phrase, a prefix such as "+" , "-" for qualified terms or one of several advanced operators, such as "site:"

Search Engine Optimization Search engine optimization (SEO) is the process of affecting the visibility of a website or a web page in a search engine's "natural" or un-paid ("organic") search results.

It is the process of improving the volume and quality of traffic to a website from search engines via results.

Higher a site’s “page rank”, the more visitors it will receive from the search engine.

Google Architecture Overview

References Introduction to Google Indexing book by Google Blog.

Wikipedia.

Slide Share.

Google Blog.