Kalen Delaney

Kalen Delaney has been working with SQL Server for over 30 years, and is one of the world's most respected authorities on SQL Server and a much sought after trainer and speaker. Her book on "SQL Server Internals" is consistently cited as a must-read for aspiring SQL Server professionals.

In-Memory OLTP eBook Download

SQL Server Internals: In-Memory OLTP

In this book, Kalen Delaney explains how the 2016 In-Memory OLTP engine works, how it stores and manipulates data, and how, even with all data stored in memory and no locking or latching, it can still guarantee the ACID properties of all transactions.

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2023-04-24 (first published: )

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SQLServerCentral Article

SQL Server Concurrency: Locking, Blocking and Row Versioning

Your application can have impeachable indexes and queries, but they won't help you if you can't get to your data because another application has it locked. That's why every DBA and developer must understand SQL Server concurrency and how to troubleshoot excessive blocking or deadlocking. Kalen Delaney's book is your guide.

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2013-08-26

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SQL Server Concurrency eBook cover

SQL Server Concurrency: Locking, Blocking and Row Versioning

Your application can have impeachable indexes and queries, but they won't help you if you can't get to your data because another application has it locked. That's why every DBA and developer must understand SQL Server concurrency and how to troubleshoot excessive blocking or deadlocking. Kalen Delaney's book is your guide.

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2012-10-02

3,691 reads

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The Disabled Index

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Server-Level Table sizes

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Question of the Day

The Disabled Index

I run this code on SQL Server 2022.

CREATE TABLE Drink
(
    drinkid INT NOT NULL
        CONSTRAINT DrinkPK PRIMARY KEY CLUSTERED,
    drinkname VARCHAR(20),
    rating NUMERIC(2, 1)
)
GO

INSERT INTO Drink
(
    drinkid,
    drinkname,
    rating
)
VALUES
(1, 'Margarita', 4.5),
(2, 'Mojito', 4.3),
(3, 'Old Fashioned', 4.7),
(4, 'Martini', 4.4),
(5, 'Cosmopolitan', 4.2)
GO
ALTER INDEX drinkpk ON dbo.drink DISABLE
GO
SELECT * FROM dbo.Drink
GO
What is the result?

See possible answers