Esat Erkec

Esat Erkec
Latest posts by Esat Erkec (see all)
Listing temporary tables in tempdb database

How to drop temp tables in SQL Server

March 23, 2020 by

Temporary tables, also known as temp tables, are widely used by the database administrators and developers. However, it may be necessary to drop the temp table before creating it. It is a common practice to check whether the temporary table exists or not exists. So, we can eliminate the “There is already an object named ‘#temptablename’ in the database” error during the temporary table creation.

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Downloading the SQL Server 2019 Express install package

How to install SQL Server Express edition

January 16, 2020 by

What is SQL Server Express edition?

SQL Express is a free and feature-limited edition of SQL Server that has been being published since the SQL Server 2005 version and it still continues to be published by Microsoft. Nowadays, Microsoft has released the Express edition of SQL Server 2019. We can use this edition for lightweight data-driven mobile, desktop or web applications. However, when we decide to use this edition, the supported features have to be checked in the Editions and supported features of SQL Server 2019. For example, the database size can not exceed 10 GB and the SQL Server Agent feature is not supported by the Express editions. As a result, we must take the limited features into consideration before planning to use the SQL Express Editions.

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Introduction to the sp_executesql stored procedure with examples

January 9, 2020 by

The sp_executesql is a built-in stored procedure in SQL Server that enables to execute of the dynamically constructed SQL statements or batches. Executing the dynamically constructed SQL batches is a technique used to overcome different issues in SQL programming sometimes. For example, when we want to determine the displayed columns in our reports, this procedure might be a solution option for us. In the simplest sense, this procedure takes a dynamically constructed SQL batch and other parameters, then execute it in the runtime and, finally, it returns the result.

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An overview of the STRING_AGG function in SQL

January 3, 2020 by

In this article, we will explore the STRING_AGG function in SQL and we will also reinforce our learning with various examples. STRING_AGG function can be counted as a new member of the SQL aggregation functions and it was announced in SQL Server 2017. STRING_AGG function gathers all expression from rows and then puts it together in these rows expression in order to obtain a string. Additionally, this function takes a separator parameter that allows separating the expressions to be concatenated.

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SQL Variables: Basics and usage

November 18, 2019 by

In this article, we will learn the notions and usage details of the SQL variable. In SQL Server, local variables are used to store data during the batch execution period. The local variables can be created for different data types and can also be assigned values. Additionally, variable assigned values can be changed during the execution period. The life cycle of the variable starts from the point where it is declared and has to end at the end of the batch. On the other hand, If a variable is being used in a stored procedure, the scope of the variable is limited to the current stored procedure. In the next sections, we will reinforce this theoretical information with various examples

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SQL multiple joins for beginners with examples

October 16, 2019 by

In this article, we will learn the SQL multiple joins concept and reinforce our learnings with pretty simple examples, which are explained with illustrations. In relational databases, data is stored in tables. Without a doubt, and most of the time, we need a result set that is formed combining data from several tables. The joins allow us to combine data from two or more tables so that we are able to join data of the tables so that we can easily retrieve data from multiple tables. You might ask yourself how many different types of join exist in SQL Server. The answer is there are four main types of joins that exist in SQL Server. First of all, we will briefly describe them using Venn diagram illustrations:

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Renaming the temp tables

How to rename tables in SQL Server with the sp_rename command

October 7, 2019 by

In this article, we will learn to rename tables in SQL Server. sp_rename is a built-in stored procedure which helps to rename user tables in the SQL Server. During the software development life cycle, we might be faced with various scenarios that required to rename the existing tables in the database. For example, the tables which are created in the SQL Server might be needed to be renamed, because of the software version upgrades, bug fixing or other various development requirements. These and similar reasons can make renaming tables important. So, in this article, we will particularly focus on how to rename the tables in SQL Server.

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