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lite-log powershell

Script to Start Multiple Virtual Machines

25 views   0 comments last modified about 9 days ago

The following is a PowerShell code snippet to start multiple VMs through vmplayer.exe: # Navigate to the folder where vmplayer.exe file exists cd "D:\Program Files (x86)\VM Player" # Start the VMs by using vmplayer...

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teradata

Useful DBC (Data Base Computer) System Views in Teradata

17 views   0 comments last modified about 9 days ago

This page summarize some of the commonly used views in Teradata. Conventions In all the views in the following sections, X views are also available though they only return rows that contain information on objects that the requesting database user owns, created, granted privilige on,...

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lite-log hadoop hdfs

Resolve Hadoop RemoteException - Name node is in safe mode

16 views   0 comments last modified about 14 days ago

In Safe Mode, the HDFS cluster is read-only. After completion of block replication maintenance activity, the name node leaves safe mode automatically. If you try to delete files in safe mode, the following exception may raise: org.apache.hadoop.ipc.RemoteException(org.apac...

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hadoop hdfs parquet sqoop

Configure Sqoop in a Edge Node of Hadoop Cluster

71 views   0 comments last modified about 14 days ago

This page continues with the following documentation about configuring a Hadoop multi-nodes cluster via adding a new edge node to configure administration or client tools. ...

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hadoop yarn

Configure YARN and MapReduce Resources in Hadoop Cluster

10 views   0 comments last modified about 14 days ago

When configuring YARN and MapReduce in Hadoop cluster, it is very important to configure the memory and virtual processors correctly. If the configurations are incorrect, the nodes may not be able to start properly and the applications may not be able to run successfully. For example...

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sql server lite-log

A New SQL Server Client Tool - SQL Operations Studio

27 views   0 comments last modified about 14 days ago

If you have used Visual Studio Code, you probably will also enjoy a new client tool SQL Operations Studio. Currently it is available as preview version and not formally released yet. What is SQL Operations Studio SQL Operations Studio is a data management tool that enables working w...

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hadoop yarn hdfs

Configure Hadoop 3.1.0 in a Multi Node Cluster

312 views   0 comments last modified about 15 days ago

Previously, I summarized the steps to install Hadoop in a single node Windows machine. Install Hadoop 3.0.0 in Windows (Single Node) In this page, I...

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lite-log

Install Big Data Tools (Spark, Zeppelin, Hadoop) in Windows for Learning and Practice

157 views   2 comments last modified about 21 days ago

Are you a Windows/.NET developer and willing to learn big data concepts and tools in your Windows? If yes, you can follow the links below to install them in your PC. The installations are usually easier to do in Linux/UNIX but they are not difficult to implement in Windows either since the...

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hadoop yarn hdfs

Default Ports Used by Hadoop Services (HDFS, MapReduce, YARN)

45 views   0 comments last modified about 28 days 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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sql server spark hdfs parquet sqoop

Load Data into HDFS from SQL Server via Sqoop

42 views   0 comments last modified about 2 months ago

This page shows how to import data from SQL Server into Hadoop via Apache Sqoop. Prerequisites Please follow the link below to install Sqoop in your machine if you don’t have one environment ready. ...

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sqoop

Install Apache Sqoop in Windows

37 views   0 comments last modified about 2 months ago

This page summarizes the steps required to install Apache Sqoop (v1.4.7) in Windows 10 environment. What is Sqoop Sqoop is an ETL tool for Hadoop,which is designed to efficiently transfer data between structured (RDBMS), semi-structured (Cassandra, Hbase and etc.) and unstructured ...

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sql server zeppelin

Connecting Apache Zeppelin to your SQL Server

47 views   0 comments last modified about 2 months ago

This page demonstrates the steps you need to connect to SQL Server in Zeppelin. There are many ways to implement this, for example SQL Server interpreters in GitHub. In this page, I am going to use the JDBC driver to connect to SQL Server instead of using third party interpreters. For authe...

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lite-log linux

Mount Windows Shared Folder in SUSE or other Linux VMware Guest

14 views   0 comments last modified about 2 months ago

This page summarizes the steps to mount a windows shared folder in a Linux VMware guest machine, i.e. SUSE. Setup shared folder In Virtual Machine Settings windows, add shared folder. ...

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lite-log powershell

Calculate Time Difference between Dates in PowerShell

34 views   0 comments last modified about 3 months ago

PowerShell provides a number of cmdlets to retrieve current date time and to create time span object. Calculate time difference - CmdLets $current = Get-Date $end= Get-Date $diff= New-TimeSpan -Start $current -End $end Write-Output "Time difference is: $di...

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lite-log spark hdfs scala parquet

Write and Read Parquet Files in HDFS through Spark/Scala

232 views   0 comments last modified about 3 months ago

In my previous post, I demonstrated how to write and read parquet files in Spark/Scala. The parquet file destination is a local folder. Write and Read Parquet Files in Spark/Scala In this page...

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spark scala parquet

Write and Read Parquet Files in Spark/Scala

145 views   2 comments last modified about 3 months 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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Querying Teradata and SQL Server - Tutorial 1: The SELECT Statement

27823 views   7 comments last modified about 4 years ago

SELECT is one of the most commonly used statements. In this tutorial, I will cover the following items: Two of the principal query clauses—FROM and SELECT Data Types Built-in functions CASE expressions and variations like ISNULL and COALESCE. * The functio...

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Install Teradata Express 15.0.0.8 by Using VMware Player 6.0 in Windows

11512 views   23 comments last modified about 4 years ago

In this article, I am going to introduce how to install Teradata Express in virtual machines in Windows. Download software 1) Download VMware Player for Windows 32-bit and 64-bit from the following link (version 6.0): ...

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Working with SQL Server Compact 4.0 using Entity Framework 6 and ADO.NET

10219 views   0 comments last modified about 4 years ago

SQL Server Compact 4.0 (CE 4.0) is a free SQL Server embedded database ideal for building standalone and occasionally connected applications for mobile devices, desktops, Web clients and others. In one of my projects, I used it as the database for logging errors, which assumes the errors will onl...

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Generate Formatted Excel Destination (Output) in SSIS Data Flow Task

8034 views   0 comments last modified about 4 years ago

SSIS (SQL Server Integration Service) provides a number of convenient tasks to enable data integration. Exporting data from database to Excel file is a common task in ETL (Extract, Transform, Load) projects. Constantly the users/customers may raise format request regarding the Excel extract. To g...

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Create ETL Project with Teradata through SSIS

7676 views   2 comments last modified about 3 years ago

Infosphere DataStage is adopted as ETL (Extract, Transform, Load) tool in many Teradata based data warehousing projects. With the Teradata ODBC and .NET data providers, you can also use the BI tools from Microsoft, i.e. SSIS. In my previous post, I demonstrated how to install Teradata Tool...

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dotnet core angular asp.net core 2

Issue - Unable to get property 'apply' of undefined or null reference occurred in Angular 4.*, VS2017 15.3, ASP.NET Core 2.0

5728 views   10 comments last modified about 2 years ago

Issue Context After installed Visual Studio 2017 15.3 preview and .net core 2.0 preview SDK, I upgraded one of my existing asp.net core project to 2.0. The project was created using ‘dotnet new angular’ SPA template.  I also upgraded all the client app packages to the latest. For exa...

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Connect to Teradata Virtual Machine Guest from Windows Host

5261 views   16 comments last modified about 4 years ago

In my previous posts about Querying Teradata and SQL Server, I logged into the virtual machine graphic interface to manage the database. However, I constantly found it is resource intensive as there is only 4GB memory in my laptop. Instead, I will use text mode to start the virtual machine and co...

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java kerberos

Java Kerberos Authentication Configuration Sample & SQL Server Connection Practice

4146 views   2 comments last modified about 3 years ago

Overview Recently, I have been working on an ETL framework to load various source data (i.e. files, SQL Server, Oracle and Teradata) into Teradata. Due to some limitations, Java was chosen as the implementation language though IBM Infosphere DataStage is available to use. DataStage has p...

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[C#] Connect to Teradata Database via .NET Data Provider

3866 views   2 comments last modified about 3 years ago

In this post, I will demonstrate how to connect to Teradata database via .NET Data Provider for Teradata using C#. Prerequisites Install the .NET Data Provider for Teradata from the following link: ...

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Resolve the Issues in Upgrading Entity Framework to Version 6.1

3662 views   0 comments last modified about 4 years ago

When upgrading your Entity Framework to Entity Framework 6.1 (EF6) from version 5.0, you may meet a number of issues. I have summarized all the issues I’ve encountered and their resolutions for your reference. Upgrade to EF6 Microsoft has provided one summary about upgrading to E...

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Create and Debug C/C++ Programs with Eclipse and Cygwin in Windows

3072 views   0 comments last modified about 3 years ago

In this post, I am going to demonstrate how to use Eclipse to create and debug C/C++ programs for Unix/Linux in Windows. I am going to use Cygwin GCC as toolchains. Cygwin GDB will also be installed for debugging purpose. I am using Windows 10 and JRE 1.8 in the following steps. Install E...

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asp.net core 2

Server.MapPath Equivalent in ASP.NET Core 2

2840 views   0 comments last modified about 8 months ago

In traditional asp.net applications, Server.MapPath is commonly used to generate absolute path in the web server. However, this has been removed from ASP.NET Core. So what is the equivalent way of doing it?

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Querying Teradata and SQL Server - Tutorial 2 Filtering and Sorting

2765 views   2 comments last modified about 4 years ago

Tutorial –1 For Teradata developers, if you have no SQL Server installed, please go to the following link to download the SQL Server 2014 Expression Edition. ...

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Querying Teradata and SQL Server - Tutorial 0: Preparation

2576 views   0 comments last modified about 4 years ago

In this serial, I will compare Teradata SQL with T-SQL with samples provided. This is mainly prepared for SQL Server DBAs, Developers and other users to help them quickly master the common used SQLs in Teradata platform. Similar to T-SQL, Teradata SQL implements most part of the ANSI SQL with ext...

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Surface RT/Pro 版本Windows 8 QQ下载与安装

2451 views   0 comments last modified about 5 years ago

Surface的用户可能会遇到一个难题,在应用商城里边无法搜索到QQ应用程序。但是让我疑惑的是,我的Windows 8.1 系统之前是成功安装了QQ。

后来在腾讯QQ下载官网发现,其实是有QQ应用安装的链接:

按照如下方法安装Surface QQ.

Have fun!

image

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Migrate from Universal Membership Provider to ASP.NET Identity 2.1.0 - PasswordHarsher

2166 views   2 comments last modified about 4 years ago

In my previous post, I demonstrated how to migrate from ASP.NET Universal Membership Provider to ASP.NET Identity 2.1.0. ...

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about 9 days ago

@Ansh

Yes, you can.

For example, the following code is used to read parquet files from a Hadoop cluster.

def readParquet(sqlContext: SQLContext) = {
// read back parquet to DF
val newDataDF = sqlContext.read.parquet("hdfs://hdp-master:19000/user/hadoop/sqoop_test/blogs")
// show contents
newDataDF.show()
}

The cluster was setup by following this post:

Configure Hadoop 3.1.0 in a Multi Node Cluster

Of source the hdp-master:19000 needs to be accessible from the server that running the Spark/Scala code.

At the moment, my HDFS is set as readable for all servers/users in the LAN. In a production environment, you may need to manage the permissions too.

Furthermore, you can also run Spark apps in a Spark Cluster instead of in stand-alone or local machine.  I will cover more about this in my future post.

about 9 days ago

Can we connect and read remotely located HDFS Parquet file? by using above code

about 3 months ago

@Neil S

No need to apology. I don't have one VM with Windows 7 so I could not verify for you.

I was about to suggest you to create one issue in the GitHub and then I just noticed you already did that.

https://github.com/steveloughran/winutils/issues/9 

Let's see how the author would response. 

The WinUtils project source code is available here:

https://github.com/apache/hadoop/tree/f67237cbe7bc48a1b9088e990800b37529f1db2a/hadoop-common-project/hadoop-common/src/main/winutils 

You may want to debug it in your system (if you have Visual Studio installed). More specifically, the source code for the command you are invoking is available here:

https://github.com/apache/hadoop/blob/f67237cbe7bc48a1b9088e990800b37529f1db2a/hadoop-common-project/hadoop-common/src/main/winutils/systeminfo.c

If I am using Windows 7, I could actually help you to debug.

about 3 months ago

@Raymond Tang

I have to apologize, I missed the point that you mentioned Windows 10 as the work environment at the begining of the tutorial, so the tutorial is not applied to Windows 7 64 bit.

I'm really sorry about my mistake.

about 3 months ago

@Raymond Tang

If you ran the command on Windows 10 and you didn't find any problems, then it doesn't contradict with what I wrote and the tutorial is relevant for Windows 10, but if the command "winutils systeminfo" returns the error when running on Windows7 64 bit then it may be beneficial noticing some requirenments in the tutorial that Hadoop 3.0.0 can only be installed on Windows 10 at the moment untill the issue with winutils.exe is not solved for Windows7 64 bit, due to the reason that winutils.exe for Hadoop 3.0.0 still doesn't on Windows7 64 bit.

about 3 months ago

@Neil S

I have run the command in my system. I didn't get any issue.


about 3 months ago

@Raymond Tang

I followed all the steps to setup. The problem is played back on Windows7 64bit. If you try issuing a command "winutils systeminfo" in the directory where winutils.exe for Hadoop 3.0.0 is located you will receive an error responce. This does not happen if you do the same with winutils for hadoop 2.6.4 or 2.7.x for instance but unfortunately this version of the executable file is not suitable for Hadoop 3.0.

about 3 months ago

@Neil S.

The machine I am using is Windows 10 64 bit and it is working properly all the time.

Did you follow all the steps to setup?

about 3 months ago

Unfortunately the issue with the missing winutils.exe in the binary distributive of Hadoop 3.0.0 cannot be solved. The file windows.exe downloaded from the above mentioned mentioned resource causes an error when run with the parameter systeminfo on Windows7 64 bit. The text of the error is PdhAddCounter \Network Interface(*)\Bytes Received/Sec failed with 0xc0000bb8.
Error in GetDiskAndNetwork. Err:1

about 3 months ago

@Raju

In which step you could not type password? In this tutorial, there are two places:

  • Logon to suse  (use Ctrl +Alt to release mouse cursor, for more details about VMware shortcuts, refer to this page)
  • Connect to Teradata database in Teradata Studio Express.

about 3 months ago

i installed teradata in vmware player.but i am unable to type password. it is not taking input to password.please anyone help me.where am going wrong.

about 5 months ago

Version 3.0 beta1 is now available.