Category : T-SQL - SentryOne Team Blog

Category: T-SQL

Slides and Scripts: Baltimore SQL Server User Group

Slides and Scripts: Baltimore SQL Server User Group

Get the slides and Transact-SQL demo scripts from my recent presentation at the Baltimore SQL Server user group meeting.

Paul White : Properly Persisted Computed Columns

Paul White : Properly Persisted Computed Columns

Paul White (@SQL_Kiwi) walks through a new trace flag in SQL Server 2016 designed to yield better execution plans (and performance) for queries involving computed columns.

Paul White : UNION ALL Optimization

Paul White : UNION ALL Optimization

Paul White (@SQL_Kiwi) digs into row goals as he explains some interesting and inconsistent behavior with UNION ALL.

SQL Server Optimizer Secrets With Trace Flag 86xx

SQL Server Optimizer Secrets With Trace Flag 86xx

Kevin Kline (@kekline) provides his slides and scripts from his new SQLBits session describing the deep internals exposed by the 86xx series of trace flags.

Derik Hammer : Myths : Table variables are always in-memory

Derik Hammer : Myths : Table variables are always in-memory

Guest author Derik Hammer (@SQLHammer) dismisses the common myth that table variables perform better than #temp tables because they are always in memory.

A new series on performance-related SQL Server myths

A new series on performance-related SQL Server myths

Aaron Bertrand (@AaronBertrand) begins a new series aimed at debunking common myths about SQL Server performance.

Rob Farley : Using AT TIME ZONE to fix an old report

Rob Farley : Using AT TIME ZONE to fix an old report

Rob Farley (@rob_farley) contributes to T-SQL Tuesday #87, showing how he would use AT TIME ZONE to simplify reports based on an end user's time zone.

T-SQL Tuesday #87 : Shiny New Toys

T-SQL Tuesday #87 : Shiny New Toys

For T-SQL Tuesday #87, Aaron Bertrand (@AaronBertrand) talks about two shiny new toys used for disassembling and reassembling strings: STRING_SPLIT() and STRING_AGG().

Follow-up #1 on leading wildcard seeks

Follow-up #1 on leading wildcard seeks

Aaron Bertrand (@AaronBertrand) shows how to implement simple triggers that maintain trigram-type tables used for better supporting wildcard searches.

One way to get an index seek for a leading %wildcard

One way to get an index seek for a leading %wildcard

In an effort to make leading wildcard searches sargable, Aaron Bertrand plays around with a trigram-type implementation in SQL Server.

Performance Surprises and Assumptions : GROUP BY vs. DISTINCT

Performance Surprises and Assumptions : GROUP BY vs. DISTINCT

Aaron Bertrand acknowledges that DISTINCT and GROUP BY are usually interchangeable, but shows there are cases where one performs better than the other.

Bad Habits Revival

Bad Habits Revival

Aaron Bertrand (@AaronBertrand) breathes some new life into his long-running SQL Server series on bad habits and best practices. The latest installment discusses the various impacts of choosing GUIDs over numeric types for keys.

Photo credit: badgreeb_records

SQL Server v.Next : STRING_AGG Performance, Part 2

SQL Server v.Next : STRING_AGG Performance, Part 2

Aaron Bertrand (@AaronBertrand) starts digging deeper into the performance of string concatenation methods STRING_AGG and FOR XML PATH.

SQL Server v.Next : STRING_AGG() performance

SQL Server v.Next : STRING_AGG() performance

Aaron Bertrand takes an initial look at the performance of a new function, STRING_AGG, in SQL Server v.Next CTP 1.1.

Can comments hamper stored procedure performance?

Can comments hamper stored procedure performance?

After a recent conversation on Twitter, Aaron Bertrand shows where excessive comments in your stored procedures might have an impact on performance.