SentryOne Team Blog (blogs.sentryone.com)

Category : T-SQL

Itzik Ben-Gan : T-SQL bugs, pitfalls, and best practices – subqueries

Itzik Ben-Gan : T-SQL bugs, pitfalls, and best practices – subqueries

Itzik Ben-Gan resumes his blog series on T-SQL bugs, pitfalls, and best practices, treating an issue with correlated column references in subqueries.

Sharing two T-SQL slide decks from CodeStock

Sharing two T-SQL slide decks from CodeStock

Aaron Bertrand shares his slide decks and demos from two recent presentations at CodeStock in Knoxville, TN.

Itzik Ben-Gan : Row Pattern Recognition in SQL

Itzik Ben-Gan : Row Pattern Recognition in SQL

Itzik Ben-Gan asks you to invest in SQL Server's future by voting for Row Pattern Recognition, a potential T-SQL syntax extension he deems the next step in the evolution of window functions.

Paul White : IGNORE_DUP_KEY slower on clustered indexes

Paul White : IGNORE_DUP_KEY slower on clustered indexes

Paul White explains why the IGNORE_DUP_KEY index option on a clustered index can result in much poorer performance than for a nonclustered unique index.

Filtered Indexes and INCLUDEd Columns

Filtered Indexes and INCLUDEd Columns

Rob Farley talks about filtered indexes and when you might want to add filtered columns to the index definition.

Itzik Ben-Gan : T-SQL bugs, pitfalls, and best practices – determinism

Itzik Ben-Gan : T-SQL bugs, pitfalls, and best practices – determinism

Itzik Ben-Gan starts a new blog series on T-SQL bugs, pitfalls, and best practices, leading off with some common issues involving determinism.

Itzik Ben-Gan : Closest Match, Part 3

Itzik Ben-Gan : Closest Match, Part 3

Itzik Ben-Gan reviews the logic and performance of user submissions to a reader challenge involving joining between two tables based on closest match.

Itzik Ben-Gan : Closest Match, Part 2

Itzik Ben-Gan : Closest Match, Part 2

Itzik Ben-Gan reviews the logic and performance of user submissions to a reader challenge involving joining between two tables based on closest match.

Jonathan Kehayias : Improve Performance of UDFs with NULL ON NULL INPUT

Jonathan Kehayias : Improve Performance of UDFs with NULL ON NULL INPUT

Jonathan Kehayias shows why it can be beneficial to use the RETURNS NULL ON NULL INPUT option for scalar UDFs.

Itzik Ben-Gan : Closest Match, Part 1

Itzik Ben-Gan : Closest Match, Part 1

Itzik Ben-Gan starts a new multi-part series on solving a reader challenge involving joining between two tables based on closest match.

Itzik Ben-Gan : Understanding log buffer flushes

Itzik Ben-Gan : Understanding log buffer flushes

Itzik Ben-Gan explains log buffer flushes and shows how to use them to help balance performance, transaction size, and durability.

Itzik Ben-Gan : Reader solutions to Special Islands challenge

Itzik Ben-Gan : Reader solutions to Special Islands challenge

Itzik Ben-Gan steps through an interesting reader submission for his "Special Islands" challenge from last month, with some surprising performance implications.

Itzik Ben-Gan : Special Islands

Itzik Ben-Gan : Special Islands

Itzik Ben-Gan explains the mechanics behind some different approaches to solving gaps and islands problems in T-SQL.

T-SQL Tuesday #106 : INSTEAD OF triggers

T-SQL Tuesday #106 : INSTEAD OF triggers

For this month's T-SQL Tuesday, Aaron Bertrand shows that when triggers are necessary, in some cases INSTEAD OF triggers can be better for performance than AFTER triggers.

Itzik Ben-Gan : Optimization Thresholds : Grouping and Aggregating Data, Part 5

Itzik Ben-Gan : Optimization Thresholds : Grouping and Aggregating Data, Part 5

In the conclusion of his series on grouping and aggregation costs, Itzik Ben-Gan reveals some of the math behind seek vs. scan decisions.