john_wong_ca@hotmail.com

John Huang, Microsoft Certified Master in SQL Server, SQL Server MVP, is an independent SQL Server consultant in Vancouver BC, Canada. He started using SQL Server for his projects in year 1994. He has architected and implemented many SQL and BI applications serving different industrial areas. He loves talking about SQL Server and discussing SQL Server technologies with others. He blogs at http://www.sqlnotes.info.

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SQL Server +0 and -0

by john_wong_ca@hotmail.com

John Huang’s Blog

This is a very interesting error happened in one of my clients’ databases. Their database has been running for at...

2013-04-30

1,563 reads

SQL Saturday #198 Feb 16, 2013

by john_wong_ca@hotmail.com

John Huang’s Blog

SQL Saturday 198, http://www.sqlsaturday.com/198/ ; is coming to Vancouver Feb 16 this year. As of now, 56 sessions are collected from...

2013-01-09

821 reads

NULL Values Impact the Performance of MAX() and MIN()

by john_wong_ca@hotmail.com

John Huang’s Blog

We know that we need to take special attention about NULL values while writing queries because they may lead us into...

2012-12-26

2,326 reads

Inserted and Deleted are One Table?

by john_wong_ca@hotmail.com

John Huang’s Blog

Inserted and deleted tables are 2 pseudo tables preseting the before and after images of modified rows. They can only...

2012-10-17

2,430 reads

Update with UPDLOCK

by john_wong_ca@hotmail.com

John Huang’s Blog

Do you think it’s a good idea to add UPDLOCK hint to the table which will be modified in an...

2012-10-10

1,447 reads

Have You Seen This Error?

by john_wong_ca@hotmail.com

John Huang’s Blog

location: AppendOnlyVerStoreMgr.cpp:776
Expression: 0
SPID: 64
Process ID: 4912
Description: Cannot locate version record and page is not allocated. Status = 3
Msg 3624, Level 20,...

2012-09-10

1,332 reads