SQL Performance slow when accessing most recent records

Question

I have a MSSQL2005 database that has records dating back to 2004, there are currently just under 1,000,000 records in one particular table.

Thing is, if I run a repo

Answer 1

What do the execution plans look like? If different you might need to manually update statistics on the table as the newly inserted rows are likely to be disproportionately unrepresented in the statistics and it might thus choose a sub optimal plan.

See this blog post for an explanation of this issue Statistics, row estimations and the ascending date column

Additionally check that your 2011 query isn't encountering blocking due to concurrent inserts or updates that do not affect queries against historic data.