Downtime Caused by the Postgres Transaction ID Wraparound Problem
Learn about transaction ID wraparound in PostgreSQL, which caused a problem for the author.
2026-02-23 (first published: 2026-02-13)
4,888 reads
Learn about transaction ID wraparound in PostgreSQL, which caused a problem for the author.
2026-02-23 (first published: 2026-02-13)
4,888 reads
Learn about filtered indexes in SQL Server, how they work, and how they can help improve performance.
2025-11-24
4,755 reads
Learn about unlogged tables and how they work in PostgreSQL.
2025-11-21
5,260 reads
Learn about a MySQL feature that could be useful in some scenarios for SQL Server.
2025-11-10
4,320 reads
Learn about implicit transaction and why you might not want to enable this setting.
2025-10-24
6,711 reads
Learn how a setting an improve high concurrency inserts with the OPTIMIZE_FOR_SEQUENTIAL_KEY option.
2025-10-01
6,650 reads
Learn how a trace flag affects SQL Server reading from disk and where this might be a useful thing for you to enable.
2025-09-24
2,505 reads
A look at window functions in SQL and how they can be used to query data without the restrictions of a GROUP BY.
2025-09-12
7,127 reads
Page splits are an often-overlooked performance killer in SQL Server. In this article, we take a forensic look at how serial inserts differ from mid-table inserts, revealing why inserting rows out of order causes hidden page splits, increased IO, and fragmentation. Using a wide-column table, we demonstrate both scenarios and decode their impact with page-level analysis.
2025-09-02 (first published: 2025-08-05)
2,636 reads
TEXT, NTEXT, and IMAGE columns have been deprecated for nearly two decades, yet they still silently haunt many SQL Server environments. This article explains their hidden limitations with practical demos and shows why migrating to VARCHAR(MAX), NVARCHAR(MAX), and VARBINARY(MAX) is critical for modern performance, maintainability, and future upgrades.
2025-09-02 (first published: 2025-08-06)
3,087 reads
By James Serra
Once again there were a number of Microsoft Build announcements related to data and...
A good week ago I hosted the monthly T-SQL Tuesday blog party. I invited...
By Steve Jones
I was messing around with SQLCMD and I realized something I hadn’t known. I’ve...
I have an issue where I have a Bill of Material list of items...
Comments posted to this topic are about the item Follow Your Hunch
Comments posted to this topic are about the item What Happens When You Ask...
I have a SQL Server 2022 English default installation on a server. I want to detect if there are any upper case characters in rows and I have this code:
SELECT CustomerNameID,
CustomerName
FROM dbo.CustomerName
WHERE CustomerName = LOWER(CustomerName)
Here is the sample data I am testing with:
CustomerNameID CustomerName 1 John Smith 2 Sarah Johnson 3 MICHAEL WILLIAMS 4 JENNIFER BROWN 5 david jones 6 emily davis 7 Robert Miller 8 LISA WILSON 9 christopher moore 10 Amanda TaylorHow many rows are returned? See possible answers