Synchronous VS Asynchronous Statistics Updates
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One of the things I’ve been able to implement to help with performance is changing from Update Statistics Synchronous to Auto Update Statistics Asynchronously. It’s a simple change that can have a big impact when implemented in highly transactional OLTP environments. Notice I said OLTP not OLAP, since data in an OLAP environment tends to not be as dynamic, so it’s rare to enable this in a data warehouse. So, what’s the difference between the two and why does it help? Synchronous (defaulted as AUTO_UPDATE_STATISTICS =TRUE) By default, when Auto Update Statistics is set to True, the SQL Server Query Optimizer… Continue Reading