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
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
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
Although SQL Server Data Tools (SSDT) encourages 'disconnected' database development, it also provides the SQL Server Object Explorer (SSOX) tool in SSDT's Visual Studio shell to connect to a live development instance or view an SSDT project once all references have been resolved.… Read more
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
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
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
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
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
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
If you're making a report from table-based data, an MS Word document is often a good option. In the second part of his introduction to SQL Server best-practice monitoring, Laerte Junior shows how to use PowerShell scripts to create a Word-based report with colour-coded alerts where there are problems or best practices aren't being followed.… Read more
What are the scripts that a working DBA uses so often that they become part of the 'muscle memory'? Grant Fritchey asked the question on the forums of SQL Server Central. From the large response, Grant was able to pick out the ten most popular T-SQL commands, scripts, or fragments. It seems as if, despite the range of tasks we do, there are some common tools we use.… Read more
A DBA in charge of a whole lot of databases and servers has to check regularly that there are no likelihood of problems. The task is well suited for automation as workload increases. Laerte Junior introduces a PowerShell-based reporting framework that aims to simply provide a Word-based report with colour-coded alerts where there are problems or best practices aren't being followed.… Read more
In-Memory OLTP, aka Hekaton, originally shipped with 2014, and although it certainly helped the performance of certain types of workload, it then had certain restrictions that impeded its widespread adoption.With SQL Server 2016, there is more support for In-Memory OLTP and a more seamless integration with SQL Server's Database Engine. It is time to consider whether In-Memory OLTP can help those pinch-points in your data throughput, explains Artemakis Artemiou.… Read more
SQLXML isn't exactly new technology, and parts of it aren't pretty, but if you need to heave vast quantities of XML data into a SQL Server database then you may come to appreciate the raw speed of which it's capable. Adam Aspin shows how to configure the SQL XML Bulk Loader tool for optimal data loading performance.… Read more
It is important for developers and DBAs to be able to determine the interdependencies of any database object. Perhaps you need to work out what process is accessing that view you want to alter, or maybe find out whether that table-type you wish to change is being used. What are all these dependencies? How do you work out which are relevant? Phil Factor explains.… Read more
Before you deliberately use a heap in SQL Server rather than a table, it is worth understanding why a heap has such different characteristics, and therefore relative benefits and disadvantages. Forward pointers and the Page Free Space page are designed with performance in mind, but only in certain circumstances. Uwe explains why, and how heaps can be used to advantage.… Read more
Gail Shaw examines three common forms of generic SQL that can and will confuse the SQL Server Optimizer to the point that it generates and reuses very inefficient execution plans. Want to 'trick' SQL Server into performing millions of logical reads to return the data, when only are few thousand were really required? Try writing catch-all queries, or using control flow statements to create general-purpose procedures, or switching parameter values within a procedure. Just don't expect the resulting queries and procedures to perform well, or consistently. The ideal solution to the problem of generic T-SQL is not to write it, but failing that Gail demonstrates techniques such as recompiling the query on each execution, using hints, dynamic SQL, or splitting generic procedures into sub-procedures.… Read more
Before SQL Server had SQL window functions, SQL Server developers had to use all manner of tricks and algorithms to come up with ways to rapidly process large amounts of data. Do we need these techniques now that we can express a SQL task in terms of window functions? Kathi revisits a famous SQL challenge to find out… Read more
What's the best way of providing self-service business intelligence (BI) to data that is held in on-premise SQL Server? Not, it seems, Power BI 2.0 the hosted cloud service, but Power BI 2.0 Desktop. If moving your database to Azure isn't an option, Power BI 2.0 desktop could still bring smiles to the faces of your BI hotshots.… Read more
