Ali Shaik's Database Diary

 SQL Server on Linux: What You Need to Know Before Migrating Nowadays, many organizations are considering migrating their SQL Server databases from Windows to Linux. This decision is often motivated by factors such as cost and security, but before jumping into the Linux world, there are some important considerations to keep in mind. In this post, we'll explore what database administrators (DBAs) should know before choosing Linux over Windows for SQL Server deployments. We'll highlight some of the key differences between the two platforms and discuss the impact on SQL Server features and services. Understanding the Basics Before delving into the specifics, it's important to have a basic understanding of the differences between Linux and Windows. While both are operating systems, they have distinct architectures and approaches to managing system resources and services. Windows is a proprietary operating system developed by Microsoft, while Linux is an open-source operating sy...

  How are SQL Server licenses sold?       SQL Server is a popular database management system that offers a wide range of features and capabilities for organizations of all sizes. However, choosing the right licensing program for your organization can be confusing.   In this post, we'll take a closer look at the various licensing programs available for SQL Server.   Per Core Licensing Per core licensing is a popular licensing model for SQL Server. This model is based on the number of processor cores that are used to run SQL Server. Customers are required to purchase a minimum of four core licenses per processor, and additional core licenses can be purchased in packs of two.   This licensing model is ideal for organizations that need to run SQL Server on a large number of processors. It provides a more predictable licensing cost, as the license fee is based on the number of processor cores, rather than the number of users or device...

  Managing Version Store Space in SQL Server   Introduction: SQL Server's version store is an important component of its concurrency control mechanism, used to store row versions generated by transactions that use the READ COMMITTED SNAPSHOT or SNAPSHOT isolation levels. However, if the version store runs out of space, it can lead to transaction failures and other issues that can affect the stability and performance of your SQL Server database. In this blog post, we will discuss how to manage version store space in SQL Server and ensure that your database remains stable and performing optimally.   Identifying Version Store Space Issues: The first step in managing version store space is to identify if there are any issues. You can use the sys.dm_tran_version_store_space_usage Dynamic Management View (DMV) to monitor the space usage of the version store and identify if it is running low on space. This DMV returns information about the amount of space reserved an...

  Ø   Isolation levels determine how a transaction interacts with other concurrent transactions accessing the same data. Ø   SQL Server has four isolation levels: Read Uncommitted, Read Committed, Repeatable Read, and Serializable. Ø   Each isolation level provides a different balance between data accuracy, consistency, concurrency, and performance. Ø   It's important to choose the right isolation level for your transactions based on your specific requirements and potential concurrency issues. Ø   You should carefully consider the trade-offs between data accuracy, consistency, concurrency, and performance when choosing an isolation level. Ø   SQL Server allows you to change the isolation level at any time during a transaction using the SET TRANSACTION ISOLATION LEVEL statement. Isolation Level Description Example Read Uncommitted Allows transactions to read data that has been modified by other...

DBCC SHRINKFILE and DBCC SHRINKDATABASE are two SQL Server commands that allow you to shrink the size of a database or data file. This can be helpful if you have large amounts of unused space in your database that you want to reclaim. However, shrinking a database or data file can also lead to concurrency issues, especially if there are long-running transactions in progress. In the past, when encountering blockings while shrinking a database or data file, the only solution was to stop the shrinking process manually and allow the transaction to continue. This was not ideal, as it could lead to extended downtime and user frustration. With the release of SQL Server 2022, Microsoft has introduced a new feature called WAIT_AT_LOW_PRIORITY, which addresses this issue. This feature is an additional option for DBCC SHRINKDATABASE and DBCC SHRINKFILE. When you use the WAIT_AT_LOW_PRIORITY option, if a new shrink operation cannot obtain the necessary locks due to a long-running query already in ...

  1.        What is SQL Server build? 2.        What are the system DBs available in SQL Server, and what is the significance of each DB? 3.        How will you troubleshoot a log file growth issue that is causing disk space issues? 4.        What are startup parameters? 5.        What are the DBCC commands you use regularly? 6.        What are the DMVs you know, and what is the purpose? 7.        How will you troubleshoot blocking? 8.        What is the difference between locking and blocking and deadlock? 9.        What is the tail log backup, and when will it be useful? 10.    How does SQL Server identify differential backups? 11.    How will you verify logins and users usin...

  To view Microsoft documentation for SQL Server and its features, you can visit the following website: https://docs.microsoft.com/en-us/sql/sql-server/?view=sql-server-ver15 This website contains a wealth of information on SQL Server, including documentation on installation, configuration, administration, and development. It also provides information on the latest features and enhancements in each version of SQL Server. To find specific information on a particular feature or topic, you can use the search bar on the website or navigate through the different categories and sections. You can also find tutorials, videos, and other resources to help you learn more about SQL Server and its features. Overall, the Microsoft documentation website is a valuable resource for anyone working with SQL Server, whether you are a database administrator, developer, or data analyst.