The number of rows read shows how many rows a scan or seek touched, and it can be far larger than the rows it returned. This post builds a demo table, compares a scan with two seeks, and explains why a seek can still read too many rows.
DBREINDEX and MAXDOP: Use ALTER INDEX to Limit Parallelism
DBREINDEX and MAXDOP do not combine: DBCC DBREINDEX has no MAXDOP option, so it follows the server setting. This post shows the three errors, rebuilds a demo index with ALTER INDEX at different MAXDOP values, and measures the degree of parallelism each one used.
Instance Level Fill Factor or Index Level: What to Set
An instance level fill factor is a default for every index that sets none, and an index level setting wins. This post reads the setting, measures what each fill factor costs in pages and saves in page splits, and gives a plan for choosing the level.
sp_updatestats and Disabled Indexes: What Gets Updated
sp_updatestats and disabled indexes: the procedure updates statistics on disabled nonclustered indexes and skips a table whose clustered index is disabled. This post proves both, times the cost of disabled indexes against dropped ones on a million rows, and generates a targeted update that skips them.
Uniquifier: The Hidden Cost of Duplicate Clustered Keys
The uniquifier is a hidden 4-byte value that SQL Server adds to duplicate keys in a non-unique clustered index. This post measures its real cost row by row on SQL Server 2025 and shows it on the page. It also compares it with a unique key you choose yourself.
BETWEEN vs IN in SQL Server: Which One Reads Less?
BETWEEN vs IN looks like a style choice, and it is not. This post builds a demo table and measures BETWEEN, the two operators and an IN list with and without an index. It shows that BETWEEN and the operators share one plan, that IN seeks once for every value and that sparse values change the question.
SQL SERVER – Delete Statement and Index Usage
An index can help a DELETE statement locate rows to remove. A customer asked whether indexes benefit modifications alongside SELECT queries.