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local_offer python local_offer spark local_offer pyspark

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access_time 2 years ago

Data partitioning is critical to data processing performance especially for large volume of data processing in Spark. Partitions in Spark won’t span across nodes though one node can contains more than one partitions. When processing, Spark assigns one task for each partition and each worker threa...

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local_offer sqlite local_offer .net core local_offer entity-framework

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access_time 2 years ago

SQLite is a self-contained and embedded SQL database engine. In .NET Core, Entity Framework Core provides APIs to work with SQLite. This page provides sample code to create a SQLite database using package Microsoft.EntityFrameworkCore.Sqlite . Create sample project ...

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local_offer linux local_offer WSL local_offer ubuntu

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access_time 2 years ago

This page shows how to install Windows Subsystem for Linux (WSL) system on a non-system drive manually. Enable Windows Subsystem for Linux system feature Open PowerShell as Administrator and run the following command to enable WSL feature: Enable-WindowsOptionalFea...

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local_offer python local_offer spark local_offer pyspark local_offer hive

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access_time 2 years ago

From Spark 2.0, you can easily read data from Hive data warehouse and also write/append new data to Hive tables. This page shows how to operate with Hive in Spark including: Create DataFrame from existing Hive table Save DataFrame to a new Hive table Append data ...

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local_offer pyspark local_offer spark local_offer spark-2-x

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access_time 6 months ago

Spark provides rich APIs to save data frames to many different formats of files such as CSV, Parquet, Orc, Avro, etc. CSV is commonly used in data application though nowadays binary formats are getting momentum. In this article, I am going to show you how to save Spark data frame as CSV file in b...

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local_offer python local_offer spark local_offer pyspark

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access_time 12 months ago

In Spark, SparkContext.parallelize function can be used to convert Python list to RDD and then RDD can be converted to DataFrame object. The following sample code is based on Spark 2.x. In this page, I am going to show you how to convert the following list to a data frame: data = [(...

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Install Hadoop 3.2.1 on Windows 10 Step by Step Guide

local_offer windows10 local_offer hadoop local_offer yarn

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access_time 5 months ago

This detailed step-by-step guide shows you how to install the latest Hadoop (v3.2.1) on Windows 10. It also provides a temporary fix for bug HDFS-14084 (java.lang.UnsupportedOperationException INFO).

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local_offer SQL Server local_offer python local_offer spark local_offer pyspark

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access_time 2 years ago

Spark is an analytics engine for big data processing. There are various ways to connect to a database in Spark. This page summarizes some of common approaches to connect to SQL Server using Python as programming language. ...

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local_offer python local_offer spark

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access_time 2 years ago

This post shows how to derive new column in a Spark data frame from a JSON array string column. I am running the code in Spark 2.2.1 though it is compatible with Spark 1.6.0 (with less JSON SQL functions). Prerequisites Refer to the following post to install Spark in Windows. ...

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local_offer asp.net core local_offer identity core 2

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access_time 3 years ago

The identity system in ASP.NET has evolved over time. If you are using ASP.NET Core, you probably found User property is an instance of ClaimsPrincipal in Controller or Razor views. Thus to retrieve the information, you need to utilize the claims.

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local_offer hadoop local_offer hive

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access_time 2 years ago

In this article, I’m going to demo how to install Hive 3.0.0 on Windows 10. Prerequisites Before installation of Apache Hive, please ensure you have Hadoop available on your Windows environment. We cannot run Hive without Hadoop.  ...

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local_offer spark local_offer scala local_offer parquet

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access_time 3 years ago

In this page, I’m going to demonstrate how to write and read parquet files in Spark/Scala by using Spark SQLContext class. Reference What is parquet format? Go the following project site to understand more about parquet. ...

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Install Hadoop 3.0.0 on Windows (Single Node)

local_offer hadoop local_offer yarn local_offer hdfs

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access_time 3 years ago

This page summarizes the steps to install Hadoop 3.0.0 on your Windows environment. Reference page: https://wiki.apache.org/hadoop/Hadoop2OnWindows ...

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local_offer spark local_offer pyspark local_offer partitioning

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access_time 2 years ago

In my previous post about Data Partitioning in Spark (PySpark) In-depth Walkthrough , I mentioned how to repartition data frames in Spark using repartition ...

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local_offer hadoop local_offer yarn local_offer hdfs

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access_time 3 years ago

This page summarizes the default ports used by Hadoop services. It is useful when configuring network interfaces in a cluster. Hadoop 3.1.0 HDFS The secondary namenode http/https server address and port. ...

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Featured sites

Apache Spark installation guides, performance tuning tips, general tutorials, etc.

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Articles about Apache Hadoop installation, performance tuning and general tutorials.

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Code snippets for various programming languages/frameworks.

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Articles about ASP.NET Core 1.x, 2.x and 3.x.

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Tutorials and information about Teradata.

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