I am having a little issue in understanding how to implement a good maintenance plan in updating statistics. I have more than one db with very big tables and modifications done every day. I know for sure that the Auto Upate Statistics is not enough for our performance, so i need to update them mannually.
From all the material found online, i managed to get two queries: one for updating all the statistics created for indexes and one for updating all the statistics auto-created.
For updating the statistics for indexes, i use a query from sys.sysindexes, sys.objects and sys.schemas, by finding a percentage between the rowmodctr and rowcnt columns. Based on this percentage, i update the statistics. Also, i use STATS_DATE to update all old statistics.
For updating the auto-created statistics, the column statistics, i use a query that checks the column modified_count from sys.system_internals_partition_columns. I did not found a lot of documentation on this system internal view, so i don't really know how exactly can i analyse the column modified_count to know which statistic need to be updated.
How can analyse the field modified_count from sys.system_internals_partition_columns so that i could find out which statistic needs to be updated?
Or, is there another way i could analyse every auto-created statistics (columns statistics) so i can know which one should be updated?