A Fine Slice Of SQL Server
2. Use the Hex Code
If you know the ASCII Code of your qualifier, you can use it starting with “_x” and ending with “_”.
A ” would be described by “_x0022_” for example.
Click through for the other two, as well as a bonus side-by-side German translation.
Comments closedNiko Neugebauer looks at memory requirements for rebuilding and reorganizing columnstore indexes:
To spare all the Wows & how can’s, Microsoft was well aware of this problem and has delivered a solution with Cumulative Update 3 for SQL Server 2016 with Service Pack 1:
FIX: SQL Server 2016 consumes more memory when you reorganize a columnstore index, and here it is – a new trace flag 6404 (documented in the link and thus should be supported), that will allow you to lower the memory requirements for the ALTER INDEX … REORGANIZE command.
Let’s take it for the test, by once again running the setup workload for the FactOnlineSales_Reindex table and then executing the following command, enabling the Trace Flag 6404 and then reorganising our Clustered Columnstore Index:
This is a rather interesting post and once again makes me wish that clustered columnstore indexes could be rebuilt online.
Comments closedPaul Randal describes a few things that can change behind the scenes when you run a SELECT query:
Statistics Update
If the database property Auto Update Statistics is set to True, when a query is being compiled and a necessary statistic is determined to be out-of-date, it will be automatically updated before optimization continues, thus changing the database. Your SELECT statement could cause this to happen. Additionally, if the Auto Update Statistics Asynchronously property is enabled, the statistic will be automatically updated, but after the optimization process (so the compiling query doesn’t have to wait).
Read on for a few more activities.
Comments closedErin Stellato describes two Query Store trace flags:
Microsoft maintains a list of supported trace flags and I noticed that there are two new ones related to Query Store: 7745 and 7752. The descriptions for these Query Store Trace Flags are pretty straight-forward, but for those of you not familiar with Query Store, I thought I’d provide some context and details.
Click through for the descriptions of these two trace flags.
Comments closed