Introduction to Temporary Tables in SQL Server

A temporary table in SQL Server, as the name suggests, is a database table that exists temporarily on the database server. A temporary table stores a subset of data from a normal table for a certain period of time.

Temporary tables are particularly useful when you have a large number of records in a table and you repeatedly need to interact with a small subset of those records. In such cases instead of filtering the data again and again to fetch the subset, you can filter the data once and store it in a temporary table. You can then execute your queries on that temporary table. Temporary tables are stored inside “tempdb” which is a system database. Let’s take a look at how you can use a temporary data in a simple scenario.

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LinqToSolr – use LINQ to obtain data from Solr

Due to the fact that in my company, Solr was chosen as a full-text search platform, there appeared a strong desire to simplify the work with Solr queries using LINQ expressions.

Having surfed the Internet for alternatives, I came to the conclusion that at the moment I do not have the required library to be publicly available. The maximum I managed to find is a very partial implementation of Solr.NET queries (and the skeptic comment of the author himself).

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Specification Design Pattern in C#

In computer programming, the specification pattern is a particular software design pattern, whereby business rules can be recombined by chaining the business rules together using boolean logic. The pattern is frequently used in the context of domain-driven design.

In short, the main benefit of using “specifications” is a possibility to have all the rules for filtering domain model objects in one place, instead of a thousand of lambda expressions spread across an application.

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Why Using Unit Tests is a Great Investment into High-Quality Architecture

I have decided to write this article in order to show that unit tests are not only a tool to grapple with regression in the code but is also a great investment into a high-quality architecture. In addition, a topic in the English .NET community motivated me to do this. The author of the article was Johnnie. He described his first and last day in the company involved in the software development for business in the financial sector. Johnnie was applying for the position – of a developer of unit tests. He was upset with the poor code quality, which he had to test. He compared the code with a junkyard stuffed with objects that clone each other in any unsuitable places. In addition, he could not find abstract data types in a repository: the code contained only binding of implementations that cross request each other.

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CombGuid: Generation of SQL Server-friendly Guid Values in .NET Applications

Usage of UUID as a primary key for tables has a bunch of pros, including the option to retrieve IDs for objects created in a client application on its own without calls to the database server. However, usage of UUID as a primary key has a con: GUIDs generated by the client application may be not quite SQL Server-friendly that can lead to the overhead during the addition of a new record. Read More