An introduction to the Rollup Clause in SQL Server, which aggregates at several levels of a hierarchy. A population table by country, state and city shows how.
SQL Server emergency? Email pinal@sqlauthority.com with URGENT in the subject line.
Data Mining Algorithms (Analysis Services – Data Mining)
I quite often receive requests for the Data Mining Algorithms details. Book Online has wonderful resources for the same. I suggest to read them here.
geometry STOverlaps: Intersection Alone Is Not Enough
geometry STOverlaps asks a narrower question than whether two shapes share any points. I test equal and contained regions alongside a partial overlap. Those intersecting cases do not all satisfy the method’s overlap definition.
SQL SERVER- IF EXISTS(Select null from table) vs IF EXISTS(Select 1 from table)
Is IF EXISTS(Select null from table) faster than IF EXISTS(Select 1 from table)? A great comment thread by Divya, Brian and Marko answers it.
SQL SERVER – Recompile Stored Procedure at Run Time
Two ways to recompile a stored procedure at run time in SQL Server: add WITH RECOMPILE when you create it, or ask for a one-time recompile.
Mapping MySQL Data Types to SQL Server
Mapping MySQL data types requires checking signed ranges, text encoding, date limits, and application behavior before choosing SQL Server columns.
SQL SERVER – Plan Recompilation and Reduce Recompilation – Performance Tuning
Plan recompilation hurts performance just like a first compile. Learn what causes it, from schema changes to SET options, and how to reduce recompilation.
SQL Server slow? Let's fix it together in about four hours.
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You keep every script, and the know-how to fix it yourself next time.
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Who We Are
Pinal Dave is an SQL Server Performance Tuning Expert and independent consultant with over 24 years of hands-on experience. He holds a Masters of Science degree and numerous database certifications.
Pinal has authored 19 books and 125 Pluralsight courses. To freely share his knowledge and help others build their expertise, Pinal has also written more than 5,800 database tech articles on his blog at https://blog.sqlauthority.com.
Pinal is also a CrossFit Level 1 Trainer (CF-L1) and CrossFit Level 2 Trainer (CF-L2).
Nupur Dave is a social media enthusiast and an independent consultant. She primarily focuses on the database domain, helping clients build short and long-term multi-channel campaigns to drive leads for their sales pipeline.
Shaivi Pinalkumar Dave is a book author and a women’s artistic gymnast.

