Posts by Brent Ozar

How about a nice cup of Standard Edition?

SQL Server 2019 is out…now.

SQL Server 2019
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After just one release candidate, Microsoft has decided it’s ready to go, apparently! Well, kinda: the official build in the release notes is 15.0.2000.5, and there’s already a “servicing update” to 15.0.2070.41. I’m not sure I wanna know what’s going on there. Anyhoo, SQL Server 2019 is available for download now. This also means it’s…
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How to Think Like the SQL Server Engine: What’s the Tipping Point?

In our last episode, I’d expanded our query to include DisplayName and Age – two columns that weren’t in our nonclustered index: Transact-SQL SELECT LastAccessDate, Id, DisplayName, Age FROM dbo.Users WHERE LastAccessDate > '2018-09-02 04:00' ORDER BY LastAccessDate; 1234 SELECT LastAccessDate, Id, DisplayName, Age  FROM dbo.Users  WHERE LastAccessDate > '2018-09-02 04:00'  ORDER BY LastAccessDate; So as a result,…
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How to Think Like the SQL Server Engine: What’s a Key Lookup?

In our last couple of queries, we’ve been using a simple query to find the Ids of everyone who accessed the system since mid-2014: Transact-SQL SELECT Id FROM dbo.Users WHERE LastAccessDate > '2014-07-01' ORDER BY LastAccessDate; 1234 SELECT Id  FROM dbo.Users  WHERE LastAccessDate > '2014-07-01'  ORDER BY LastAccessDate; But Ids alone aren’t all that useful – so let’s…
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How to Think Like the SQL Server Engine: Adding a Nonclustered Index

When we left off in the last post, our users kept running this query, and they want it to be really fast: Transact-SQL SELECT Id FROM dbo.Users WHERE LastAccessDate > '2014/07/01' ORDER BY LastAccessDate; 1234 SELECT Id   FROM dbo.Users   WHERE LastAccessDate > '2014/07/01'   ORDER BY LastAccessDate; Let’s pre-bake the data by creating a copy of…
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How to Think Like the SQL Server Engine: The Perils of SELECT *

In our last post, we ran a query with an ORDER BY, but we only got one column in the SELECT: Transact-SQL SELECT Id FROM dbo.Users WHERE LastAccessDate > '2014/07/01' ORDER BY LastAccessDate; 1234 SELECT Id   FROM dbo.Users   WHERE LastAccessDate > '2014/07/01'   ORDER BY LastAccessDate; The estimated cost was about $18 Query Bucks because SQL…
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How to Think Like the SQL Server Engine: Adding an ORDER BY

We started out the How to Think Like the Engine series with a simple query with a WHERE clause: Now let’s add an ORDER BY: Transact-SQL SELECT Id FROM dbo.Users WHERE LastAccessDate > '2014/07/01' ORDER BY LastAccessDate; 1234 SELECT Id   FROM dbo.Users   WHERE LastAccessDate > '2014/07/01'   ORDER BY LastAccessDate; Here’s the updated plan – note…
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Pocket Square

Updated First Responder Kit and Consultant Toolkit for September 2019

This month’s release has a lot of new feature goodness: the Consultant Toolkit can automatically upload the results to Amazon S3, plus sp_BlitzCache adds a new sort order to better catch unparameterized queries burning up CPU, a new warning for selects that are doing writes (other than >500MB spills, which we’ve been warning you about…
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Live Class Season Pass

DBA Training Plan 22: Where to Learn More

Whew. We’ve worked through a couple dozen posts together in this DBA Training Plan, and you’re still just getting warmed up. First, pick your specialty. Here’s some of the more popular specializations in the SQL Server business: Production administration – managing uptime, building new boxes, troubleshooting clusters, setting up storage, designing virtualization infrastructures Performance tuning…
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