We are constructing a data warehouse that initially will be 1 TB and will grow around 20gigs every month.
For certain tables we are doing daily ETL processes and others we are doing weekly/monthly.
When there is a data import going into a table, is it necessary to drop and recreate the indexes?
Is there ever a point to dropping and recreating indexes or are they automatically updated?
The statistics are set to update automatically.
Thank you so much for your help and guidance.
I got this genius script:
SELECT 'ALTER INDEX [' + ix.name + '] ON [' + s.name + '].[' + t.name + '] ' + CASE WHEN ps.avg_fragmentation_in_percent > 40 THEN 'REBUILD' ELSE 'REORGANIZE' END + CASE WHEN pc.partition_count > 1 THEN ' PARTITION = ' + cast(ps.partition_number as nvarchar(max)) ELSE '' END FROM sys.indexes AS ix INNER JOIN sys.tables t ON t.object_id = ix.object_id INNER JOIN sys.schemas s ON t.schema_id = s.schema_id INNER JOIN (SELECT object_id, index_id, avg_fragmentation_in_percent, partition_number FROM sys.dm_db_index_physical_stats (DB_ID(), NULL, NULL, NULL, NULL)) ps ON t.object_id = ps.object_id AND ix.index_id = ps.index_id INNER JOIN (SELECT object_id, index_id, COUNT(DISTINCT partition_number) AS partition_count FROM sys.partitions GROUP BY object_id, index_id) pc ON t.object_id = pc.object_id AND ix.index_id = pc.index_id WHERE ps.avg_fragmentation_in_percent > 10 AND ix.name IS NOT NULL
Do you suggest I run this script daily and based on the findings run the generated code?