What’s a Key Lookup?
One of the easiest things to fix when performance tuning queries are Key Lookups or RID Lookups. The key lookup operator occurs when the query optimizer performs an index...
2019-04-17 (first published: 2019-04-03)
735 reads
SQL in the City Streamed is Today
You can still register, but join me later today for SQL in the City Streamed, along with Grant, Kathi, and Kendra. We’re all in the Redgate Software office today...
2019-04-03
35 reads
File and file group method testing for VLDB very large database
File and file group VLDB very large database....
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2019-04-03
51 reads
Validation activity in Azure Data Factory - Traffic light of your operational workflow
(2019-Apr-02) Last week Microsoft introduced a new Validation activity task to the Azure Data Factory (ADF) - https://docs.microsoft.com/en-us/azure/data-factory/control-flow-validation-activity Initially, I was confused by its name, thinking that it would help me...
2019-04-16 (first published: 2019-04-03)
11,166 reads
Isolation Levels in SQL Server
Do your eyes start to cross whenever you think about isolation levels? Mine did, too. Here's how I keep it all straight.
2019-04-03
53 reads
Activate Conference 2019: Three Days of Tech Learning
Thursday April 4 I'll be giving a workshops at the super-slick-branded Activate Conference 2019 in Baton Rouge at the Louisiana Technology Park, a conference filled with people and topics...
2019-04-02
18 reads
Group By Conference is Back April 11th!
I have joined forces with Blyther Morrow & Daniel Hutmacher to keep the GroupBy Virtual Conference going. We’re aiming to host the conference at least twice this year, and...
2019-04-02
17 reads
Group By Conference is Back April 11th!
I have joined forces with Blyther Morrow & Daniel Hutmacher to keep the GroupBy Virtual Conference going. We’re aiming to host the conference at least twice this year, and...
2019-04-02
14 reads
Group By Conference is Back April 11th!
I have joined forces with Blyther Morrow & Daniel Hutmacher to keep the GroupBy Virtual Conference going. We’re aiming to host the conference at least twice this year, and...
2019-04-02
127 reads
SQL Server 2019 Suspend/Resume TDE
Yes, a really nice new shiny feature where we have the ability to suspend and resume the encryption scan for TDE – Transparent Data Encryption which is available in...
2019-04-02
175 reads
Blogs
Announcements from the Microsoft Fabric Community Conference — Barcelona 2026
By James Serra
Microsoft shared a broad set of Fabric, Power BI, and SQL updates at FabCon...
Au Revoir for now
By Steve Jones
No, I’m not quitting or retiring. Just going on vacation, but I leave tonight...
Forums
Let's Talk Certifications
Comments posted to this topic are about the item Let's Talk Certifications, which is...
The Hidden Security Risks of Role Combination in SSAS Tabular
Comments posted to this topic are about the item The Hidden Security Risks of...
The Empty Aggregate
Comments posted to this topic are about the item The Empty Aggregate
Question of the Day
The Empty Aggregate
I have this table in a SQL Server 2025 database:
CREATE TABLE [dbo].[CustomerOrder] ( [OrderID] [int] NULL, [CustomerID] [int] NULL, [total] [money] NULL ) ON [PRIMARY] GOWhat is returned from this code? (answers are for the sum and then the count)
SELECT SUM(total) AS sum,
COUNT(total) AS count
FROM dbo.CustomerOrder;
See possible answers