Articles tagged

07 December 2017
07 December 2017

SQL Server Internals: In-Memory OLTP

In this book Kalen Delaney introduces and explains how the 2016 In-Memory OLTP engine works. The Hekaton internals knowledge offered in this book will help you migrate existing tables or databases to Hekaton, and get faster performance from your SQL Server applications than you ever thought possible.… Read more
16 March 2016
16 March 2016

The SQL Server 2016 Query Store: Forcing Execution Plans using the Query Store

The SQL Server 2016 Query Store can give you valuable performance insights by providing several new ways of troubleshooting queries, studying their plans, exploring their context settings, and checking their performance metrics. However, it can also directly affect the performance of queries by forcing Execution Plans for specific queries.… Read more
15 March 2016
15 March 2016

Creating a Date Dimension in a Tabular Model

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As well as its multidimensional model, SQL Server Analysis Services (SSAS) now has a tabular model of database that either runs in-memory or in DirectQuery mode. The in-memory analytics engine allows the users of Excel or Power View to base reports on tabular model objects. Having shown how to handle date-based information using the Multi-dimensional model, Dennes now turns his attention on the in-memory tabular model.… Read more
07 March 2016
07 March 2016

When AUTO_UPDATE_STATISTICS Doesn’t Happen

When your SQL Server database is set to have its statistics automatically updated, you will probably conclude that, whenever the distribution statistics are out-of-date, they will be updated before the next query is executed against that index or table. Curiously, this isn't always the case. What actually happens is that the statistics only gets updated if needed by the query optimiser to determine an effective query plan.… Read more
24 February 2016
24 February 2016

Azure SQL Data Warehouse

Azure SQL Data Warehouse is a fully-managed and scalable cloud service. It is still in preview, but solid. Not only is it compatible with several other Azure offerings, such as Machine Learning and Data Factory, but also with various existing SQL Server tools and Microsoft products. It talks Power BI. Are we now seeing the final piece of the Azure jigsaw fall into place?… Read more
11 February 2016
11 February 2016

Documenting SQL Server with PowerShell

SQL Server instances are generally poorly-documented. How easily can you tell if something has changed? How easily can you check that there is adequate space for growth? Are you up-to-date with licenses? What errors are happening? Who has accessing the system? Before PowerShell, it was difficult to be on top of all this. Now you can, with the help of Sander's database documenter.… Read more
27 January 2016
27 January 2016

SQL Server System Views: The Basics

When maintaining or refactoring an unfamiliar database, you'll need a fast way to uncover all sorts of facts about the database, its tables, columns keys and indexes. SQL Server's plethora of system catalog views, INFORMATION_SCHEMA views, and dynamic management views contain all the metadata you need, but it isn't always obvious which views are best to use for which sort of information. Many of us could do with a simple explanation, and who better to provide one than Rob Sheldon?… Read more
26 January 2016
26 January 2016

The SQL Server 2016 Query Store: Accessing Query Store Information Using DMVs

The SQL Server 2016 Query Store provides several new ways of troubleshooting queries, studying their plans, exploring their context settings, and checking their performance metrics. In using the Query Store to ensure that performance is as good as possible, it isn't long before it becomes important to be familiar with the DMVs that are associated with the query store, and using them in custom queries.… Read more
06 January 2016
06 January 2016

The SQL Server 2016 Query Store: Built-in Reporting

One of the most important features of the SQL Server 2016's new Query Store is the reporting. With these features, it is now possible to get a wealth of information on how your query workload is performing, either aggregated for the entire query workload or for a single query. With this information, you can see the effects of 'forcing' an execution plan for specific queries and get feedback of the consequences.… Read more
15 December 2015
15 December 2015

JSON support in SQL Server 2016

At last, SQL Server has caught up with other RDBMSs by providing a useful measure of JSON-support. It is a useful start, even though it is nothing like as comprehensive as the existing XML support. For many applications, what is provided will be sufficient. Robert Sheldon describes what is there and what isn't.… Read more
16 November 2015
16 November 2015

Doing a SQL Server Healthcheck via PowerShell

PowerShell is an ideal tool for doing health checks of a collection of SQL Server instances, and there are several examples around, but few acknowledge the fact that individual DBAs have their own priorities for tests, and need something easily changed to suit circumstances. Omid's health check allows tests to be SQL or PowerShell and requires only adding, altering or deleting files in directories. … Read more
16 November 2015
16 November 2015

The SQL Server 2016 Query Store: Overview and Architecture

SQL Server's Query Store, introduced in SQL Server 2016, helps to troubleshoot query performance by capturing a range of information about query usage, CPU, memory consumption, I/O and execution time, and retaining every Execution Plan for analysis. Much of this information is available through queries. It looks set to be the most significant enhancement of SQL Server 2016.… Read more
16 November 2015
16 November 2015

SQL Server Data Tools (SSDT) and Database References

SQL Server Data Tools (SSDT) provides, via the DacPac, interesting support for verifying not only those references within the database, but also those to other databases even if they are on other servers. Although it is adds an extra level of complexity to deployments, it can increase the probability that deployments will succeed without errors due to broken references or binding errors.… Read more
02 November 2015
02 November 2015

SQL Server Heaps, and Their Fragmentation

In SQL Server, heaps are rightly treated with suspicion. Although there are rare cases where they perform well, they are likely to be the cause of poor performance. If a table is likely to have a large number of changes, then it can become fragmented due to way that space is allocated and forward pointers used. How does one detect this problem? Is it significant? How does one deal with it, if necessary?… Read more