Expensive queries by query_hash are ranked by total cost, not by single plans. A demo runs one lookup with 40 different literals and shows that the top single plan is a scan, while the grouped total, ranked by reads, points at the lookup. The query ranks by reads, CPU, time or runs.
Case-Sensitive Search – SQL in Sixty Seconds #158
Earlier I wrote a blog post about SQL SERVER – Case-Sensitive Search. Lots of people said I should make a video on this topic.
Case-Sensitive WHERE Clause: COLLATE Without Losing the Seek
A case-sensitive WHERE clause needs a COLLATE on the comparison, but the obvious version scans the index. A demo measures 286 reads against 2, and shows two fixes: keep the plain test beside it, or give the column a case-sensitive collation.
SQL SERVER – Data and Index Compression – Real-World Conversation
Index Compression needs workload measurements of storage, I/O and CPU. A customer conversation prompted my earlier advice.
Memory-Optimized Tables as a Key-Value Cache
Build a key-value cache with SCHEMA_ONLY memory-optimized tables, native get and set procedures, expiry checks, and bounded cleanup.
Top Three Wait Stats and What Each One Means
The top three wait stats in the files people sent in were CXPACKET, SOS_SCHEDULER_YIELD and ASYNC_IO_COMPLETION. A small demo makes each wait happen and measures it with session wait statistics. The post explains what each one means and what to check next.
Wait Stats for Performance – SQL in Sixty Seconds #157
I finally decided to create a video on that topic on my SQL in Sixty Seconds Channel. I will create more videos on the topic Wait Stats for Performance.