Cardinality Estimation for a Predicate on a COUNT Expression
Paul White takes you on an optimizer journey, exploring how SQL Server comes up with cardinality estimates for COUNT queries.
2017-05-17
3,222 reads
Cardinality Estimates
Bad Cardinality Estimates from SSMS Plans – Redux
Aaron Bertrand shares some insight about early changes to Plan Explorer that help to provide you with the most accurate information we can.
2016-04-04
2,780 reads
Fixing Gatekeeper Row Cardinality Estimate Issues
The Query Optimiser needs a good estimate of the number of rows likely to be returned by each physical operator in order to select the best query plan from the most likely alternatives. Sometimes these estimates can go so wildly wrong as to result in a very slow query. Joe Sack shows how it can happen with SQL Queries on a data warehouse with a star schema.
2012-12-10
1,163 reads
Blogs
Migrate datetime data to datetimeoffset with AT TIME ZONE
By Will Assaf
I recently reviewed, worked on, and added a similar example to the DATETIMEOFFSET Microsoft...
The Comprehensive Guide to Mastering Your SQL DBA Skills
Database administrators (DBAs) are the backbone of data-driven organizations. If you're looking to break...
Friday Basics: Authentication vs. Authorization
By Brian Kelley
Another security fundamentals topic is authentication versus authorization. For those who have a clear...
Forums
The Backup File Extension
Comments posted to this topic are about the item The Backup File Extension
Ingest and Retrieve data from an ADX Cluster Using Python
Comments posted to this topic are about the item Ingest and Retrieve data from...
The DBAccountant
Comments posted to this topic are about the item The DBAccountant
Question of the Day
The Backup File Extension
I run this command in SQL Server 2022. What is the extension of the backup file?
BACKUP DATABASE HerdofTwo TO DISK = 'HerdOfTwo_20240501'See possible answers