SQL is a declarative language where each query declares what we want, but it doesn’t say how. The how is what affects the efficiency of queries. SQL performance tuning can be an incredibly difficult task, especially when working with large-scale data where even the most minor change can have a drastic impact on the query performance. When you are dealing with such huge tables, optimization is the key. An inefficient query may pose a burden on the database’s resources, and cause slow performance or loss of service for other users if the query contains errors. …

Unstructured data in the form of text: chats, emails, social media, survey responses is present everywhere today. Text can be a rich source of information, but due to its unstructured nature it can be hard to extract insights from it.

Text classification is one of the important task in supervised machine learning (ML). It is a process of assigning tags/categories to documents helping us to automatically & quickly structure and analyze text in a cost-effective manner. It is one of the fundamental tasks in Natural Language Processing with broad applications such as sentiment-analysis, spam-detection, topic-labeling, intent-detection etc.

In this article…

SQL or Structured Query Language is one of the most in-demand skills that you require whether you’re applying for a data analyst, a business intelligence engineer, a data scientist or a data engineer role. Today, SQL is the standard means of manipulating and querying data in relational databases. In this article, I will be walking you through the best SQL courses, blogs, tutorials, & books for learning SQL.

Learning SQL can be hard enough without navigating through thousands of articles & websites. …

Fig1: Most affected countries over time (based on Confirmed Cases)


The largest global pandemic since the 1918 Spanish Flu is upon us today. The novel coronavirus is bringing countries to a halt and causing widespread health impacts and fatalities. The evolution of this virus is one of the most dangerous problems for society. In this article, I’ve attempted to take a closer look at the data and trends to analyze worldwide COVID-19 cases and mortality statistics across countries.

In this article, I will walk you through the steps I undertook for this analysis with code snippets and visuals. You can…

Vijaya Rani

Business Intelligence Engineer @Amazon https://www.linkedin.com/in/vijayarani/

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