Last Backup Time comes from recorded history, which I check by backup type. Recovery still needs the files and a tested chain.
Find the Last Read and Write Time of Every Table in SQL Server
Find the last read and write time of every table in SQL Server with sys.dm_db_index_usage_stats. The tests show what counts as a read, why an insert counts as a write, what an index rebuild does to the numbers, and what wipes them.
SQL SERVER – Find Total Number of Transactions on Interval
How many Transactions run on your server per minute? A handy script reads sys.dm_os_performance_counters twice with a WAITFOR DELAY between the reads.
Monitoring Availability Group Health
Monitor availability group health through replica connection state, database synchronization, send and redo queues, and failover readiness checks.
SQL SERVER – Find Queries using Parallelism from Cached Plan
A script by Feodor Georgiev that finds queries using parallelism from the cached plan, along with their plans. Please avoid running it on a busy production server.
SQL SERVER – Index Levels, Page Count, Record Count and DMV – sys.dm_db_index_physical_stats
How many pages does an index use, and how many B-Tree levels does it have? sys.dm_db_index_physical_stats shows index levels, page count and record count.
SQL SERVER – Data Pages in Buffer Pool – Data Stored in Memory Cache
What is in your memory cache? A query on sys.dm_os_buffer_descriptors shows the data pages in buffer pool for each table and index.