Question: If they can change the join hints to improve the performance of the query. Well, the reality is that I always Avoid Join Hints.
Group by Query Hash: Find One Query With Many Plans
Group by query hash to add up every cached copy of one query. See why the top query hides across entries in SQL Server.
One Query Many Plans – SQL in Sixty Seconds #171
After the blog post, lots of people asked me it will be more helpful if I can create a video on the same topic of one query many plans.
Same Query Plan, Different Cache Entry in SQL Server
The same query plan can sit in the cache many times when query text changes by a space, a letter case or a comment. See it, measure it and learn how to share one entry.
Change Join Type for a Query: HASH, LOOP and MERGE Hints
To change join type for a query, add one of three hints to its OPTION clause. This post runs one join with each hint on two filters and compares the join type and the logical reads. It shows that no join type is best in general, and what a join hint in the FROM clause does to the join order.
Threads With Zero Rows in a Parallel Plan, Measured
A parallel plan can show threads with zero rows, and that is normal. This post reads the per-thread row counters of two real plans on SQL Server 2025 and shows where the empty threads come from. It also says when an empty thread points to a real problem.
Top 1 and Index Scan: A Scan That Stops After One Row
Top 1 and index scan can sit in the same plan, and the scan still reads only a few pages. This post runs six queries on a table of 100,000 rows and reads their logical reads. It shows why TOP 1 reads three pages in one case and every page in another.