SQL Server

[Video] Office Hours 2017/06/28 (With Transcriptions)

This week, Erik, Tara, and Richie discuss performance and load testing tools, sysadmin update SQL server restart, defragmenting column store indexes, Amazon Redshift, installing Microsoft updates, Always On Availability Groups, Redgate SQL Clone, as well as their thoughts on the current DBA job market. Here’s the video on YouTube: You can register to attend next week’s Office…
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There’s Something Funny About Variable Assignment

Guess who I’m going to give you three queries, and you have to guess what the output will be before you run them. Here they are: Transact-SQL DECLARE @DatabaseName NVARCHAR(256) = N'' SELECT @DatabaseName = d.name FROM sys.databases d WHERE d.name = 'master' AND compatibility_level = 130 ORDER BY d.database_id PRINT @DatabaseName SELECT @DatabaseName =…
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Pocket Square

[Video] Office Hours 2017/06/21 (With Transcriptions)

This week, Brent, Erik, Tara, and Richie discuss cross-database transactions in AGs, agent job owners, column store indexes, linked servers, migrating SQL Server databases to AWS cloud, synchronous readable secondary, rebuilding indexes, backups using SANs, licensing, Always On Availability Groups on CDC, Azure Cosmo DB, compression, and encryption. Here’s the video on YouTube: You can…
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Do SQL Server 2017’s Adaptive Joins Work with Cross Apply or Exists?

I think I’ve mentioned that the most fun part of new features is testing them with old ideas to see how they react. It occurred to me that if Adaptive Joins didn’t work with APPLY, I might cry. So, here goes nothin’! Cross Simple Cross Apply…ies can use Adaptive Joins, though at first glance there’s…
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SQL Server 2017: Interleaved MSTVFs Vs Inline Table Valued Functions

But is it faster? Now, I know. There are very few “always” things out there in SQL Server. This is also true for functions. A lot of the time — I might even say most of the time, inline table valued functions are going to be faster that scalar and multi statement table valued functions.…
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SQL Server 2017: Interleaved Execution for MSTVFs

What I don’t want you to take away from this Is that I want you to start using Multi Statement Table Valued Functions all over the place. There are still problems with them. Backed by table variables Lots of hidden I/O cost Number of executions may surprise you One important current limitation (May-ish of 2017)…
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[Video] Office Hours 2017/05/10 (With Transcriptions)

This week, Tara and Richie discuss increasing the size of tempdb, splitting database across several files, tracking DML changes to a table, upgrading different versions of service packs, recommendations for improving T-SQL skills, trace flags, replication, Always On Availability Groups, compatibility level of databases,  and more… Here’s the video on YouTube: You can register to…
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Breaking: SQL Server 2016 SP1 CU2 Supports ENABLE_PARALLEL_PLAN_PREFERENCE Hint

Hot Diggety! After reading an excellent tip by Dmitry Pilugin about the new hint for forcing a parallel plan in SQL Server 2017, I figured I’d test it out on SQL Server 2016’s latest CU to see if it had been back ported yet. Good news! It has. Obviously. That’s the title of the blog…
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SQL Server 2017: Statistics Information Comes To Query Plans

Warm fuzzies I think this is how my mom would have felt if I went to college. You see, once you stop cargo culting around index fragmentation, and disk queue length, you start to realize which things are actually important to query performance. Things like statistics, and cardinality estimation. And, sure, having the right indexes…
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