Capping a runaway report with Resource Governor uses workload groups, pools, and a tested classifier to limit one workload safely.
Columns With No Statistics: Read Each Warning
A columns-with-no-statistics warning needs a column-by-column investigation. Compare warning lists before and after targeted statistics creation, and check the actual query behavior before deciding that a missing statistic caused poor performance.
No Join Predicate: Verify the Relationship Before Tuning
No join predicate prompts a relationship check. Compare all combinations with exact customer-order pairs before changing indexes or hiding duplicates.
Your First Extended Events Session
Build your first Extended Events session for slow SQL calls, choose a bounded ring buffer or file target, and read the captured result.
APPROX_COUNT_DISTINCT in SQL Server: Saves Memory, Not Time
APPROX_COUNT_DISTINCT counts distinct values with almost no memory. Tested on 5 million rows, it was within 2.2 percent of the exact count and needed no memory grant, while COUNT(DISTINCT) asked for 436 MB. It was not faster.
Adaptive Joins: When the Plan Picks Its Join at Run Time
Understand adaptive joins in SQL Server, read their runtime threshold, inspect the actual choice, and test a query hint safely.
user_lookups: Verify the Plan Before Adding Coverage
user_lookups helps identify where to investigate missing coverage. Compare complete query results and actual plans before adding included columns. Weigh the read benefit against storage and write costs.