Defragment index

Index fragmentation describes a situation where the physical order of the index pages is different to the logical order. The disk drive must move back and forth and search different parts of the disk to access the required data and so the disk throughput is decreased. Fragmentation increases over time as new entries are created, modified, or deleted. To correct the fragmentation, De-fragmentation operations are performed.

Daily and weekly defragmentation

The defragmentation process runs on a daily and weekly basis, after the purger runs on the Contact, QM, Data Warehouse, and Framework databases. It operates by reorganizing defragmented database indexes and free database space for featured data. The operation can take more than 10 hours.

Stored procedure

A stored procedure (maint_index_defragmentation) uses the Transact SQL DDL command: ALTER INDEX <index name> REORGANIZE to run the defragmentation process.