Query I/O over the Last Five Minutes
When faced with a SQL Server that is performing poorly, a great starting place for troubleshooting is looking at wait stats. Once you’re gathering wait stats, if you see lots of IO-related waits, you may…
Capturing Index Usage Stats
Overview Index usage stats are invaluable for evaluating performance of existing indexes. Every time an index is used by the query-engine, an internal table is updated reflecting that usage. So, every time a scan, seek,…
Backup Performance Testing
Reliable database backups are perhaps the single most important aspect of a Database Administrator’s job. The business risk from data-loss that can occur without a reliable database backup are substantial enough to bring many smaller…
Mimic Production in Development
Attempting to debug production performance problems in your development environment can be problematic in many ways, leading to a frustrating troubleshooting experience. One very common situation is the resources on the development environment are substantially…
ALTER TABLE ALTER COLUMN failed because one or more objects access this column
There are a variety of causes for the message shown in the title of this post. Manually creating statistics for a column is one such cause. This post shows how that works, and what you…
Statistics update job
SQL Server statistics are extremely important for good query performance since they provide invaluable guidelines that allow the query optimizer to pick an optimal plan. Out-of-date or non-existent statistics objects can cause excessive I/O, poor…