Java – Pivot Table using Streams

Implement a Pivot Table in Java using Java 8 Streams and Collections.

“Money may not buy happiness, but I’d rather cry in a Jaguar than on a bus.”
― Françoise Sagan

1. Introduction

Today let us see how we can implement a pivot table using java 8 streams. Raw data by itself does not deliver much insight to humans. We need some kind of data aggregation to discern patterns in raw data. A pivot table is one such instrument. Other more visual methods of aggregation include graphs and charts.

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Sort Large CSV File using SQLite

Sorting a large CSV file by loading it into SQLite. Much faster and easier to process.

“When you’re at the end of your rope, tie a knot and hold on.”
― Theodore Roosevelt

1. Review

We are trying to sort a large CSV file. The file contains a couple of million rows – not large by “big-data” standards, but large enough to face problems working with it.

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Sorting a Large CSV File

Large CSV files present a challenge when need arises to sort. Learn how to do that using a database.

“All of life is a constant education.”
― Eleanor Roosevelt, The Wisdom of Eleanor Roosevelt

1. Introduction

Let us explore some ways of sorting large data sets.

By large, I don’t mean typical “big-data” sizes – which might consist of billions of rows. Such data sets fall into the realm of “big data” which we are not exploring today. Instead I am talking of sorting a rather large CSV file – maybe a couple of million rows.

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Load XML into Mysql Using Java

Load XML into MySQL by using Java DOM Parser.

“Never memorize something that you can look up.”
― Albert Einstein

1. Introduction

XML provides the ability to represent hierarchical structure with its parent-child relationships. This enables applications to store structured data in XML for export. Importing this XML data into a database is a bit involved as we shall see in this article. You need to write code to manage the database connection. In addition you need parse the XML and isolate the data that needs to be imported.

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