Indexing

More on Column Choice and Order for Multi-column Non-Clustered Indexes

  • Article

In the last year I’ve published articles on indexes to include Indexes: When Column Selectivity Is Not Always A Requirement – SQLServerCentral and Query Optimizer Suggests Wrong Index and Query Plan -- Why? – SQLServerCentral. This article is a continuation of just how the optimizer interacts with the index wizard. We’ve all heard and read […]

4 (1)

2021-07-07

1,973 reads

Understanding CRUD Operations on Tables with B-tree Indexes, Page-splits, and Fragmentation

  • Article

Introduction Every DML transaction reads the data before it makes any changes. Not only during a SELECT query, but when you run any DML statement, insert, update, or delete, SQL Server first fetches a bunch of pages into the buffer pool locating the desired rows and changes them while synchronously writing to the transaction log […]

5 (6)

2021-05-10

3,541 reads

Indexes: When Column Selectivity Is Not Always A Requirement

  • Article

While preparing for my SQL Saturday Salt Lake City presentation, Climbing the B-Tree, I ran into one of the “word of mouth” facts that the first column of an index should be highly selective, i.e., it should only point to one or a few rows. This is not always the case and I’ll show you […]

5 (1)

2020-09-16

2,454 reads

Blogs

Daily Coping 17 Sep 2021

By

I started to add a daily coping tip to the SQLServerCentral newsletter and to...

Ethics in Modern Data at Music City Tech 2021

By

  On Sept 16, Christine and I presented our joint presentation on Ethics in Modern Data at...

Slides and Video from Building a Regret-free Foundation for your Data Factory Now Available

By

Last week, Kerry and I delivered a webinar with tips on how to set...

Read the latest Blogs

Forums

SQL 2016 SP3 CHECKDB WITH EXTENDED_LOGICAL_CHECKS problem.

By Ken McKelvey

This seems to be the same problem which occurred with SQL2017 CU21 and is...

Find all SPs, FNs, and VWs where particular string occurs

By Vladimir Isaev

I have this task to find all SPs, FNs, and VWs where particular string...

Excel privary levels

By V

There are three Excel privacy levels: Private, Organizational, Public. When Excel's privacy level is...

Visit the forum

Ask SSC

SQL Server Q&A from the SQLServerCentral community

Get answers