fillfactor

Fillfactor is a database storage parameter that dictates how often a page will be split. In database storage, a page refers to a single unit of storage that contains a portion of a table or index. The fill factor is a value between 0 and 100 that controls the percentage of available space on a page that can be filled with data. The default fill factor for a database can be set through various methods, including a server-wide setting or at the rowset level.

A low fill factor means more pages will be needed to store the same amount of data, which can lead to slower query performance. Conversely, a high fill factor results in fewer pages, leading to faster query performance, but will cause the database to consume more space. Spaces that are not filled are referred to as free space gaps, and these can lead to varying page sizes, reducing storage efficiency.

The choice of fill factor depends primarily on the database workload and performance requirements. Most databases allow the fill factor to be set on a per-table level, which can help manage space utilization based on usage.

Adjusting the fill factor is generally done through SQL commands, and it's essential to consider the trade-off between storage usage and query performance when deciding on an optimal fill factor. In some cases, resetting the fill factor may lead to internal fragmentation of the table, resulting in additional storage usage over time.