Introduction It was the week before Black Friday — the biggest online ad rush of the year. Our US-based ad-tech platform was gearing up for an insane traffic spike. Hundreds of real-time campaigns were about to go live across multiple brands, each with thousands of user sessions flowing through our system. Every incoming user impression […]
Take a basic look at database diagrams, what they are, and how to create one.
Unlocking Interoperability: A Guide to Foreign Data Wrappers in PostgreSQL and Aurora PostgreSQL AWS RDS As a database professional, I often encounter scenarios where data is fragmented across various systems. In today's distributed IT landscape, it's not uncommon for critical business information to reside in different databases, perhaps an on-premise PostgreSQL instance for legacy applications, […]
As with others, I've had to deal with death in the family recently. Some other family members are dealing with cancer (a few friends too). Happily none of us has recently been a disaster zone, but that's happened too. So yeah, big, nasty scary stuff happens in life. However, for most of us, most of […]
I was just reading about how the Philippines are working to update their databases in support of faster and better responses in the case of an emergency. While I do volunteer for some of the local emergency services, I'm right at the bottom of the heap as just a radio operator. I don't have any […]
In this article, I wanted to test a common assumption we DBAs make – that adding INCLUDE columns to indexes is harmless. I created a FULL recovery test database with a realistic wide Orders table containing extra large VARCHAR columns to simulate an ERP workload. I ran updates and measured transaction log backup sizes before and after adding INCLUDE columns to a nonclustered index. The results shocked me. The update without INCLUDE columns generated a 10 MB log backup, while the same update with INCLUDE columns produced over 170 MB – a 17x increase in log volume. I explain why this happens: INCLUDE columns are physically stored in index leaf rows, so updates affecting them write bigger log records. I also clarify that updating key columns generates even more log than INCLUDE updates because it involves row movement (delete + insert), but INCLUDE updates still cost more log than if those columns weren’t indexed at all. The takeaway is clear – INCLUDE columns are powerful, but they silently increase transaction log generation, impacting backup sizes, replication lag, and DR readiness. Always measure their real cost before deploying to production.
In Part 1, I explored how to bend SQL Server Agent to our will and peek under the hood of Azure SQL Managed Instance (SQL MI), gaining full OS access to the container (all without relying on xp_cmdshell). But once I realized what kind of door I'd opened, curiosity pushed us further, tempting us to […]
In this next article, we look at creating balanced dimensions on demand.
I hop in the Jeep the other day and turn on my ham radio. Have I mentioned I'm a licensed amateur radio operator? Yeah, yeah, I know. I won't shut up about it. Ha! My call sign is KC1KCE. I haven't been on HF in a while, but I'm regularly on the air locally here […]
By James Serra
I’m honored to be hosting T-SQL Tuesday — edition #192. For those who may...
By Vinay Thakur
Continuing from Day 2 , we learned introduction on Generative AI and Agentic AI,...
Quite the title, so let me set the stage first. You have an Azure...
hi everyone I am not sure how to write the query that will produce...
Comments posted to this topic are about the item Rollback vs. Roll Forward
Comments posted to this topic are about the item Foreign Keys - Foes or...
I have some data in a table:
CREATE TABLE #test_data
(
id INT PRIMARY KEY,
name VARCHAR(100),
birth_date DATE
);
-- Step 2: Insert rows
INSERT INTO #test_data
VALUES
(1, 'Olivia', '2025-01-05'),
(2, 'Emma', '2025-03-02'),
(3, 'Liam', '2025-11-15'),
(4, 'Noah', '2025-12-22');
If I run this query, how many rows are returned?
SELECT *
FROM OPENJSON(
(
SELECT t.* FROM #test_data AS t FOR JSON PATH
)
) t; See possible answers