Plan cache size shows how much memory each cached query plan takes. This post lists every plan in one database with its size, its text and its execution count. It also explains why the cache entry and the plan itself report different sizes.
Eager Index Spool: When the Plan Builds Its Own Index
Investigate an eager index spool, read seek keys and output, and compare a supporting index with the cost of rebuilding temporary storage.
How to Find Table Cardinality from the Execution Plan? – Interview Question of the Week #213
How to find table cardinality from the execution plan? I answer this health check question in two different ways, using a simple AdventureWorks query.
Does Parallel Threads Process Equal Rows? – Interview Question of the Week #211
Do parallel threads process equal rows? Usually no, and a simple AdventureWorks query with its actual execution plan proves it in a few seconds.
Implicit Conversions That Quietly Turn Seeks Into Scans
Find implicit conversions in SQL Server plans, compare parameter and column types, and fix type contracts without losing Unicode data.
Finding the Plan That Changed: Query Store Plan History
Read Query Store plan history, compare duration by interval, find plan changes, and review a temporary force with an exit plan.
The Ascending Key Problem: Estimates for Today’s New Rows
Diagnose ascending key estimates with histogram boundaries, modification counts, and controlled comparisons before updating statistics.