The Hidden Danger of Wildcard Operators In Join Operations
This article looks at one of the killers of performance at scale, SELECT *.
2026-08-14
2,198 reads
This article looks at one of the killers of performance at scale, SELECT *.
2026-08-14
2,198 reads
Dive deep into the powerful SQL window functions, LAG() and LEAD(). Explore their intricacies, discover real-world examples, and avoid common pitfalls.
2023-12-11
11,478 reads
Learn how you can use Windows Performance Monitor and the PAL to gather metrics from your SQL Server instances.
2022-07-20
25,015 reads
It’s not difficult to set up an extended event session, but reviewing and saving the data can be complex. In this article, Edward Pollack demonstrates how to collect extended event data.
2021-11-03
SQL Server perfmon counters provide a wealth of information about performance. In this article, Fabiano Amorim shows how current wisdom about one counter, SQL Compilations/sec, can sometimes be misleading.
2021-08-20
Monitoring SQL Server for performance is a critical part of a DBA’s job. In this article, Edward Pollack explains some of the SQL Server performance monitor data and how to collect it.
2021-07-21
Edward Pollack demonstrates how SQL Server plan cache mining can uncover a wealth of information to help with troubleshooting performance issues.
2021-05-21
In this article, Edward Pollack describes some of the issues when querying against remote data sources. He covers remote SQL Servers and also connecting to a PostgreSQL database.
2020-10-30
SQL Server 2014 introduces the first major redesign of the SQL Server Query Optimizer cardinality estimation process since version 7.0. The goal for the redesign was to improve accuracy, consistency and supportability of key areas within the cardinality estimation process, ultimately affecting average query execution plan quality and associated workload performance. This paper provides an overview of the primary changes made to the cardinality estimator functionality by the Microsoft query processor team, covering how to enable and disable the new cardinality estimator behavior, and showing how to troubleshoot plan-quality regressions if and when they occur.
2018-06-26
2,974 reads
Developer shops may decide to use Read Committed Snapshot Isolation (RCSI) to reduce contention, and possibly improve performance, but it is not without its own pitfalls. In this article, Uwe Ricken describes a situation where long running transactions caused a severe performance degradation when RCSI was in use.
2018-03-26
3,103 reads
A RAG pipeline that answers questions in the demo is not the same thing...
By Steve Jones
“A multitude of bad ideas is necessary for one good idea” – from Excellent...
Yesterday I gave a talk for MSSQLTips called “Building a DBA Agent for Your...
Telp/Wa 62 821-8200-233 Jl. Raya Cilandak KKO No.9, RT.1/RW.5, Ragunan, Ps. Minggu, Kota Jakarta...
Telp/Wa 62 821-8200-203 Gedung Perkantoran Hijau Arkadia, Tower C - Ground Floor, unit C103,...
Telp/Wa 62 821-8200-174 Menara Karya, Jl. H. R. Rasuna Said Ground floor, RT.1/RW.2, Kuningan,...
Which number will the COUNT() return after executing the following statements:
DROP TABLE IF EXISTS #test; CREATE TABLE #test (id INT) INSERT INTO #test (id) SELECT * FROM GENERATE_SERIES(1, 3) AS gs ; ALTER TABLE #test ADD flag BIT CONSTRAINT DF_#test_flag DEFAULT 0; go UPDATE #test SET flag = 0 WHERE id = 1 UPDATE #test SET flag = 1 WHERE id = 2 INSERT INTO #test (id) VALUES (4) SELECT COUNT(*) FROM #test AS t WHERE flag = 0See possible answers