This blog describe Index rebuild and
Reorganize.
When we right click on index we have two options - Rebuild and Reorganize
Rebuild : rebuild drops the existing index and recreates again.
alter index all on wms_loose REBUILD
Reorganise : reorganize physically arrange the leaf nodes of the index.
alter index all on wms_loose REORGANIZE
Note
If index fragmentation shows above 40%. we
should reorganize in this scenario.
And when fragmentation shows 10% to 40 %.we should rebuild in this scenario.
remember one thing the time of rebuild database resources are locked.