Yes, NOLOCK can miss rows. A row can vanish from your report while it sits safely in the table. Nobody deleted it. The read simply walked past it.
Everyone Expected AI to Come From the Big Companies
Everyone expected AI to come from the big companies. The research did come from their labs, but the products did not, and the reason is not talent or budget.
UPDATE Without WHERE Clause: The Day Everyone Got a Raise
An UPDATE without WHERE clause changed 8,432 salaries. When ROLLBACK can help, and how to check the affected row count before COMMIT.
Ten AI Phrases We Use Too Often
In 2013 I wrote a small list of phrases developers used too often. Twelve years later, here are ten AI phrases I hear every week, and what each one means.
NOLOCK: Why It Counts Some Rows Twice and Misses Others
Everybody knows NOLOCK can show uncommitted data. Far fewer know why it counts some rows twice and misses others, with nothing rolled back. Let me show you.
Tech Conferences: Five Questions About the Money
I said tech conferences are worth every hour and the sessions are not. Nobody argued about the sessions. They wrote about money instead, and five questions arrived.
Finding the Root Cause of Slow Queries
Finding the root cause of slow queries starts by separating work from waits, then testing theories against plans and history.