Sending a Query to All Databases of All Specified Servers in MS SQL Server and C#.NET

Introduction

Often, it is necessary to send a query to all databases of all specified servers. Many DML-queries can be created with built-in tools. However, what about DDL-queries?

In this article, we are going to explore an example of implementing the application that sends a query to all databases of all specified servers, using MS SQL Server and C#.NET.

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Using Expressions to Filter Data of Database

I would like to start with a description of the problem that I encountered. There are entities in the database that need to be displayed as tables on the UI. The Entity Framework is used to access the database. There are filters for these table columns.

It is necessary to write a code to filter entities by parameters.

For example, there are two entities: User and Product.

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What dangers can the update of .Net 4.6.1 to .Net 4.6.2 hide?

In this article, I would like to share a solution of unexpected problem occurred in one of the projects I am currently working on.

What dangers can the update of .Net 4.6.1 to .Net 4.6.2 hide? I thought that to avoid serious issues during the update to a minor version, it was enough to read the release notes. However, it turned out that Microsoft can make interesting and entertaining changes beyond release notes that can divert you on soulful summer nights and days off.

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Query Optimization in PostgreSQL. EXPLAIN Basics – Part 2

In my previous article, we started to describe the basics of the EXPLAIN command and analyzed what happens in PostgreSQL when executing a query.

I am going to continue writing about the basics of EXPLAIN in PostgreSQL. The information is a short review of Understanding EXPLAIN by Guillaume Lelarge. I highly recommend reading the original since some information is missed out.

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Configuration Comparison of Dependency Injection Containers (IOC)

I have often questioned myself which IoC container would be suitable for this or that project best. Their performance is only one side of the coin. The other side of the coin is the simplicity and speed of learning. So, I decided to compare the following containers from this point of view: Autofac, Simple Injector, StructureMap, Ninject, Unity, and Castle Windsor. In my opinion, these are the most popular IoC containers. You can find some of them in the list of the top 20 NuGet IoC packages. Also, I added a few containers based on my personal preferences. I really like Autofac and when writing this article I was reinforced in my choice in most of the cases.

In this article, I will describe the basics of the IoC containers, such as configuration and logging of components. I also want to compare the management of lifetime scope and advanced features. Code examples can be found in the LifetimeScopesExamples GitHub repository.

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Analysis of MS SQL Server for those who see it for the first time – Part 2

Analysis of MS SQL Server for those who see it for the first time – Part 1

We continue to analyze what is happening on our MS SQL Server. In this article, we are going to explore how to retrieve information about user performance: who makes what, and how much resources are consumed.

I think the second part will be interesting for both database administrators and developers who need to understand what is wrong with the requests on the production server that used to work fine on the test server.

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32-bit Excel and 64-bit SQL Server

What could be simpler than to get data from an Excel table in SQL Server?

There are many ways to accomplish this task. You can utilize Integration Services (former DTS) or import and export wizard, which is the same under the hood. Another way is to create a simple ADO.NET app. You can use the Linked Server mechanism, which allows you to see any ODBC / OLE DB-reachable object in the form of a table (a collection of tables) or the result of an ad hoc query.

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Upload Documents to Azure Data Lake and Export Data using SSIS

 Introduction

Azure is growing every day. Microsoft created Azure, which is a Cloud Computing service released on 2010.

According to Microsoft, 80% of the fortune 500 companies are using Azure. Also, 40% of the Azure Revenue comes from Startups and independent software vendors. 33% of the Azure Virtual Machines are using Linux. Microsoft expects to earn $20 billion in 2018.

That is why companies are migrating part of the data to Azure and sometimes all the data.

Azure Data Lake is a special storage to analyze Big Data in parallel in Azure. It is optimized for analytics. You can store Social network data, emails, documents, sensor information, geographical information and more.

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Tricky Questions about C#

Some questions may seem too basic, but they still contain tiny tricks. Sometimes even a simple question may nail to the wall. These questions will be useful to all who study the language.

So, let’s start!

1. What will be the result of execution of the following code?

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