General database design

Ahmad Yaseen

SQL Server SET Options that Affect the Query Result – SET ANSI_NULLS, SET ANSI_PADDING, SET ANSI_WARNINGS and SET ARITHABORT

June 30, 2017 by

SQL Server provides us with a number of options to control SQL Server behavior on the connection level. These session-level options are configured using the SET T-SQL command that change the option value for the session on which the SET command is executed. Changing the default value of these session-level configuration affects how the session queries will be executed affecting the query result. The performed change on a session-level option will be applied to the current session until its value is reset or until the current user’s session is terminated.

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Vitor Montalvão

Configuration, operations and restrictions of the tempdb SQL Server system database

June 28, 2017 by

Introduction

tempdb is one of the 4 system databases that exists in all SQL Server instances. The other databases are master, model and msdb. In case of using Replication, a fifth system database named distribution will also exist. You can find all existing system databases in SQL Server Management Studio (SSMS) under the Databases / System Databases folder:

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Ahmad Yaseen

SQL Server 2016 Memory-Optimized Tables – The Checkpoint operation

June 21, 2017 by

The SQL Server Database Engine stores data changes in the buffer pool, in memory, before applying it to the database files, for I/O performance reasons. After that, a special kind of background process, called Checkpoint, will write all of these not reflected pages, also known as Dirty Pages, to the database data and log files periodically.

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Neeraj Prasad Sharma

Introduction to Nested Loop Joins in SQL Server

May 8, 2017 by

A relational database system uses SQL as the language for querying and maintaining databases. To see the data of two or more tables together, we need to join the tables; the joining can be further categorized into INNER JOIN, LEFT OUTER JOIN, RIGHT OUTER JOIN, FULL OUTER JOIN, and CROSS JOIN. All these types of joins that we use are actually based on the requirement of the users.

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Prashanth Jayaram

SQL Server 2016 enhancements – SQL Truncate Table and Table Partitioning

April 18, 2017 by

The idea behind this article is to discuss the importance and the implication of SQL Partition and understand the SQL truncate command partitioning enhancements in SQL 2016

One of the biggest challenges for a DBA is to identify the right candidate for table partitioning, as it requires expertise in design and implementation.

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Ed Pollack

Implementing and Using Calendar Tables

March 24, 2017 by

Introduction

There is a common need in reporting to aggregate or return data that is crunched based on date attributes. These may include weekdays, holidays, quarters, or time of year. While any of this information can be calculated on the fly, a calendar table can save time, improve performance, and increase the consistency of data returned by our important reporting processes. In my previous article, you could learn about designing of a calendar table.

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Ed Pollack

Designing a Calendar Table

March 22, 2017 by

Introduction

There is a common need in reporting to aggregate or return data that is crunched based on date attributes. These may include weekdays, holidays, quarters, or time of year. While any of this information can be calculated on the fly, a calendar table can save time, improve performance, and increase the consistency of data returned by our important reporting processes.

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Kaloyan Kosev

How to work with filegroups in SQL Server and migrate data between them

March 8, 2017 by

As you may already have figured out, the default settings in SQL Server are not always the best. Such is the case when you are working with new user databases; usually you get a single data (*.mdf) and transaction log (*.ldf) file. The data file resides within the PRIMARY file group; the only one we have so far, and it will store all of our databases objects, system objects, user tables, user stored procedures and all other objects. In some cases this default configuration may be good enough for you, but let us cover why would you prefer a different configuration in your production environment.

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Aamir Syed

When to Use SQL Temp Tables vs. Table Variables

February 21, 2017 by

It is very beneficial to store data in SQL Server temp tables rather than manipulate or work with permanent tables. Let’s say you want full DDL or DML access to a table, but don’t have it. You can use your existing read access to pull the data into a SQL Server temporary table and make adjustments from there. Or you don’t have permissions to create a table in the existing database, you can create a SQL Server temp table that you can manipulate. Finally, you might be in a situation where you need the data to be visible only in the current session.

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Daniel Calbimonte

Are SQL Server database triggers evil?

January 25, 2017 by

Introduction

There is a lot of talk about how bad triggers are, how you should never use them, etc. I wanted to spend some time reviewing fact vs fiction and do an objective analysis of SQL Server database triggers (both DDL and DML), warts and all. We will review alternatives and compare them with triggers to determine advantages vs disadvantages of each approach.

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Best Practices for Configuring Newly Installed SQL Server Instances

January 20, 2017 by

Often we install SQL Server on clients or we get to clients where they have pre-installed SQL Server Instances. As a DBA we have the Primary responsibility of keeping the Database Up and Running. This responsibility leads to optimizing, performance tuning and many other stuff related to database’s internal objects. While keeping the other aspects in mind many of us have to go through the configuration of the newly installed or pre-installed but un-configured instances. Configuring SQL Server newly instances are not an easy task and a DBA might want to configure an Instance in many ways.

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Kimberly Killian

How to Split a Comma Separated Value (CSV) file into SQL Server Columns

December 29, 2016 by

Receiving a comma delimited file is not new technology nor is it difficult to deal with in SQL Server. As a matter of fact, it is extremely easy. There are many cases as to why you would want to do this. For example, you have an external data source that needs to be imported into your database/table. There a couple ways to do this, however the quickest and easiest way is to use the native “import” feature within SQL Server Management Studio and you can even save it to an SSIS Package at the end of the process. The end result of using this method is that the external CSV file is loaded into a SQL Server table where columns are created and rows are populated.

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Ahmad Yaseen

Understanding the SQL Server Proportional fill algorithm

November 22, 2016 by

When creating a database, SQL Server maps this database with minimum two operating system files; the database data file MDF and the database log file LDF. Logically, the database data files are created under a collection set of files that simplifies the database administration, this logical file container is called the Filegroup. Database data files can come in two types, the Primary data files that contains metadata information for the database and pointers to the other database files in addition to the data, where each database should have only one Primary data file and the optional Secondary files to store data only. The basic storage unit in SQL Server is the Page, with each page size equal to 8KB. And each 8 pages with 64KB size called Extent.

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