Sliding Partition Window Concept
Before we continue, let’s remind ourselves of what the Sliding Partition Window is and what it gets us. The whole point of the sliding window is to create a sort of data conveyor belt. New data comes into the production table and is placed in the empty partitions (and files where relevant) and the old data is “switched” or moved off to a staging table for further processing and, crucially, removal. In this way the table slides forward along its partitions but remains essentially the same size. There will always be a set number of partitions worth of data in your production table keeping it lean and fit. In addition, once you’ve moved the data from the staging tables to an archive or reporting database the physical files can be removed and your production database can be maintained at a manageable, near constant, size.