for rebuilding index, here is also a script to figure out the fragmentation and decide whether rebuilding index is in need:
use [database_name] select dbschemas.[name] as 'schema', dbtables.[name] as 'table', dbindexes.[name] as 'index', indexstats.avg_fragmentation_in_percent, indexstats.page_count from sys.dm_db_index_physical_stats (db_id(), null, null, null, null) as indexstats inner join sys.tables dbtables on dbtables.[object_id] = indexstats.[object_id] inner join sys.schemas dbschemas on dbtables.[schema_id] = dbschemas.[schema_id] inner join sys.indexes as dbindexes on dbindexes.[object_id] = indexstats.[object_id] and indexstats.index_id = dbindexes.index_id where indexstats.database_id = db_id() order by indexstats.avg_fragmentation_in_percent desc
when the avg_fragmentation_in_percent >30, please rebuild the index (alter index rebuild). if the 5 < avg_fragmentation_in_percent < 30, please reorgnize the index (alter index reorganize)
however, as you mentioned that it finished quickly, maybe you can manage it before you run the job each time. just arrange it as the preparation for you job. please update statistics each time you want to run the job.