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power-bi bigquery

Use Google Cloud BigQuery as Data Source in Power BI

37 views   0 comments last modified about 4 days ago

BigQuery is Google’s serverless data warehouse in Google Cloud. Power BI can consume data from various sources including RDBMS, NoSQL, Could, Services, etc. It is also easy to get data from BigQuery in Power BI. In this article, I am going to demonstrate how to connect to BigQuery to create...

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dotnet core lite-log

Set AttachDbFilename as Relative Path in .NET Core

14 views   0 comments last modified about 8 days ago

.NET Framework, you can use |DataDirectory| to configure connection string when connecting to SQL Server database file via attach mode: AttachDbFilename=|DataDirectory|\dbname.mdf In .NET Core, you cannot directly set SQL Server Express connec...

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dotnet core lite-log

Instantiate a Service in ConfigureServices Method in .NET Core

10 views   0 comments last modified about 8 days ago

.NET Core is built in with dependency injection. Usually method ConfigureServices in Startup class is used to register services in the container. The signature of the method looks like the following: public void ConfigureServices(IServiceC...

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kontext docu

Kontext Project is now Open Source as Docu Project

74 views   0 comments last modified about 13 days ago

Kontext project is now open source as Docu project hosted in GitHub. At the moment, only SQLite is supported and other databases will be added once version 1.0.0 is ready. SQLite is used for easy setup and testing. Prerequisites .NET Core SDK 2.1.3 .NET Core Runtime 2.1 ...

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.net core lite-log

ASP.NET Core 2.1 Error - 'Cyrillic' is not a supported encoding name

20 views   0 comments last modified about 14 days ago

After upgrading to ASP.NET Core 2.1 (.NET Core SDK 2.1.301), you may encounter the following error about encoding: System.ArgumentException    HResult=0x80070057    Message='Cyrillic' is not a supported encoding name. For information on defining a custo...

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.net core entity-framework

SQLite in .NET Core with Entity Framework Core

15 views   0 comments last modified about 17 days 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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Graphics Programming and Image Processing in .NET Core 2.x

12 views   0 comments last modified about 19 days ago

In .NET Core 2.x, Windows Forms or WPF are not implemented since they are based on GDI+ and DirectX respectively in Windows. In .NET Core 3.0, there is plan to add Desktop Packs which includes UWP. WPF and Windows Forms. However, they will still be Windows-only. In .NET Core applications, you may...

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lite-log power-bi

Data Analysis Expressions to Create Static Tables in PowerBI

37 views   0 comments last modified about 2 months ago

DATATABLE StaticTable1 = DATATABLE("IntCol",INTEGER,"StringCol",STRING,{{1,"User1"},{2,"User2"}}) The above expression generates a table with two columns IntCol and StringCol : ...

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power-bi google-analytics

Power Analytics with Power BI and Google Analytics

105 views   0 comments last modified about 2 months ago

Power BI is my favourite BI and visualization tool as it is very simple yet powerful. It doesn’t only support traditional data sources like databases, CSV, JSON, XML and etc., but also supports emerging sources that are available in HDFS, Spark, R, Salesforce, Google Analytics and cloud platforms...

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Power BI Analytics - Connect to DBMS and Card

25 views   0 comments last modified about 2 months ago

Power BI supports connecting to most of the DBMS databases such as SQL Server, Oracle, Teradata, MySQL, DB2, Sybase, Snowflake, Google BigQuery, Impala and etc. This page summarizes the steps to connect to SQL Azure and to create the following part of the sample dashboard of this series: ...

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lite-log powershell

Script to Start Multiple Virtual Machines

47 views   0 comments last modified about 2 months 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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Useful DBC (Data Base Computer) System Views in Teradata

93 views   0 comments last modified about 2 months 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

57 views   0 comments last modified about 3 months 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

210 views   0 comments last modified about 3 months 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

75 views   0 comments last modified about 3 months 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

45 views   0 comments last modified about 3 months 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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Querying Teradata and SQL Server - Tutorial 1: The SELECT Statement

28892 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 by Using VMware Player 6.0 in Windows

12091 views   23 comments last modified about 5 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

10669 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

8507 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

8180 views   2 comments last modified about 4 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 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

6420 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 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

5491 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

4544 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

4126 views   2 comments last modified about 4 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: ...

View detail core 2

Server.MapPath Equivalent in ASP.NET Core 2

4061 views   0 comments last modified about 10 months ago

In traditional 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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Resolve the Issues in Upgrading Entity Framework to Version 6.1

3848 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

3291 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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Querying Teradata and SQL Server - Tutorial 2 Filtering and Sorting

2897 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

2681 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

2569 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。


按照如下方法安装Surface QQ.

Have fun!


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hadoop yarn hdfs

Install Hadoop 3.0.0 in Windows (Single Node)

2367 views   14 comments last modified about 5 months ago

This page summarizes the steps to install Hadoop 3.0.0 in your Windows environment. Reference page: ...

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about 30 days ago

I can get it work by using the following approach:

1) Create an IIS website (http://localhost/Test/) with one page index.html:

        <h1>Test iframe</h1>
        <iframe src="http://localhost:8080/#/notebook/2D7J63CN7" width="600px" height="400px" style="border:1px solid #000000"></iframe>

2) And then open the website in the browser: http://localhost/Test/

If you open with a file URL, then the content cannot be displayed due to security reasons:


When you publish your website, your Zeppelin site should also be deployed into a server that your user can access.

about 1 month ago

Hi Raymond Tang. I come back because I tried but I didn't succeded to embed a zeppelin notebook as an iframe in my website. I have something like that  

<div id="interactivForm">

                                <iframe id="MyInterpreter" src="http://localhost:8085/#/notebook/2DHDGTVNU"></iframe>
                           </div> in my website but it doesn't work. But I can access to http://localhost:8085/#/notebook/2DHDGTVNU without problem. Do you know how to do that?
Thank you.

about 2 months ago

You can use <iframe> html element to embed Zeppelin into your website.

This also means that your Zeppelin website (*:8080 by default) needs to be exposed to all your users (i.e. their networks).

about 2 months ago

Hi Raymond. Now I don't really want to do any authentification. I want only to give an opportunity to anonymous user to execute spark in my website using zeppelin. So do you know how to do that or do you have a tutorial where I can see how to do that step by step? Thank you very much.

about 2 months ago

You can embed Zeppelin into a website.

However you need to decide how to pass through user credentials from your website to Zeppelin website depends on the authentication type. 

The authentication part you can reference to the following website: 

Based on my current understanding, I don't think currently you can directly implement the automatic logon without extending Zeppelin (but I might be wrong). 

about 2 months ago

Hi everyone,

do you know if it is possible to embed Zeppelin Notebook in a webpage? Like as an iframe or another method? So that users can come and execute their own code? Do you think that is possible? Has someone an idea to do that? Thank you!

about 2 months ago

Nw, I'm glad it worked. :)

about 2 months ago

I am sorry. It works!

about 2 months ago

I come again and sorry. When I run this commande %HADOOP_HOME%\bin\hdfs dfs -put file:///G:/DataAnalytics/test.txt / I get an error: put: `G:/DataAnalytics/test.txt': No such file or directory. But I followed the configuration step by step and my DataAnalytics folder is in G:.

about 2 months ago

Hi. thank you for your answer. I found a solution for my problem. If it can help someone, the problem was related to the syntax of my system username. It contains a space. So, to fixe it, you can edit /etc/hadoop/hadoop-env.cmd, at the end of this file, you will find set HADOOP_IDENT_STRING=%USERNAME% , change this with a string that you want but without space. For example: set HADOOP_IDENT_STRING=myuser, the problem will be fixed.

about 2 months ago

Did you follow all the steps in this post? For example, you need to ensure winutils tool is installed: 

Overwrite your bin folder (%HADOOP_HOME%\bin) with the files from this link:

The current available version is 3.0.0 and I am not very sure whether it can fix the issue for 3.0.1 but worth giving it a try.

about 2 months ago

Good morning, I am trying to install hadoop 3.0.1 in my windows but when I want to test my configuration it gives me that error: Error: Can not find or load the main class. Can someone help me please?

Thank you

about 2 months ago


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 ="hdfs://hdp-master:19000/user/hadoop/sqoop_test/blogs")
// show contents

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 2 months ago

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