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Master Data Services – The Basics

Master Data Services (MDS) is Microsoft's platform for supporting Master Data Management (MDM). A system like MDS, if properly maintained, gives organisations a powerful alternative to increasingly having to centralize databases as a way of preventing data from getting out sync or become inconsistent, and a reliable way of managing the flow of data through corporate IT systems. It makes microservice architectures realistic. Hari Yadav shows you how to get up and running with MDS.

2016-10-25

4,165 reads

External Article

PowerShell Just Enough Administration

A major difficulty for a System Administrator who wishes to provide access for auditors, Helpdesk staff, developers and other IT people is that adminstrator roles give users more access than they need. It is too easy to make mistakes, or to make more changes than those that were signed-off. With JEA, it is possible to create role-based access control (RBAC) endpoints that define precisely what actions you’ll let your users carry out without needing a elevated, privileged administrator credentials, and which log and report all operations.

2016-10-19

3,276 reads

External Article

In-Memory OLTP: Row Visibility in SQL Server’s MVCC

SQL Server's In-memory OLTP is fast, due to its multi-valued concurrency control (MVCC). MVCC avoids the need for locks by arranging for each user connected to the database to see a snapshot of the rows of the tables at a point in time, No changes made by the user will be seen by other users of the database until the changes have been completed and committed. It is conceptually simple but does the user always see the correct version of a row under all circumstances? Shel Burkow explains.

2016-10-17

3,150 reads

External Article

DELETE Operation in SQL Server HEAPs

You should stick to using tables in SQL Server, rather than heaps that have no clustered index, unless you have well-considered reasons to choose heaps. However, there are uses for heaps in special circumstances, and it is useful to know what these uses are, and when you should avoid heaps. Uwe Ricken explains, and demonstrates why you'd be unwise to use heaps rather than tables when the data is liable to change.

2016-10-14

3,646 reads

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Question of the Day

Getting the Average

I have this data in the dbo.Commission table in a SQL Server 2022 database. 

salesperson commission
Brian       12
Brian       16
Andy        7
Andy        14
Andy        21
Steve       20
Steve       NULL
All the data is a varchar, and I decide to run this query to get the totals for each salesperson. 
SELECT SalesPerson
     , AVG(TRY_PARSE(Commission AS int)) AS TotalCommission
 FROM commission
 GROUP BY SalesPerson
GO
What average commission is calculated for Steve?

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