David Wiseman

SQL DBA. Dabble in C#. Creator of DBA Dash - open source monitoring for SQL Server.
  • Interests: Running

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Blogs

Counting Groups with Window Functions: #SQLNewBlogger

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I looked at row_number() in a previous post. Now I want to build on...

The query processor ran out of internal resources and could not produce a query plan – When You’ve Managed to Confuse SQL With a Crazy IN Clause.

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Recently I received a cry for help over Teams. The issue was that an...

Extending a SQL Server Failover Cluster Across Regions in  Google Cloud Platform (GCP)

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I was the principal author of this SIOS whitepaper, which describes how to build...

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Forums

How to determine if a DB is currently being used

By dax.latchford

Hi - I'm looking for advice regarding the best & quickest way to establish...

Data cleansing/conversion tool HPE

By juliava

Hello.   I am looking for a tool Data cleansing/conversion, was recommended HPE any...

System views in a contained availability group

By mark4data

I have a query that runs in a job to check on orphaned users....

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Question of the Day

The LAGging NULL

I have this data in a SQL Server 2022 table: 

player         yearid team HR
Alex Rodriguez 2012   NYY  18
Alex Rodriguez 2013   NYY  7
Alex Rodriguez 2014   NYY  NULL
Alex Rodriguez 2015   NYY  12
Alex Rodriguez 2016   NYY  9
If I run this code, what are the results returned in the hrgrowth column? 
SELECT
  player
, yearid
, hr
, hr - LAG (hr, 1, 0) IGNORE NULLS OVER (ORDER BY yearid) AS hrgrowth
FROM dbo.playerstats;

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