Further testing suggests that the cause is SET ANSI ON!!!
In ADO SET ANSI is ON by default, I don't know if there is any way that can be changed.
Have been testing this in Fox and have discovered that with SET ANSI OFF (the Foxpro default) things are fine, well almost. However, once ANSI is set on Rushmore seems to stop working once the table gets beyond a certain size. Looking at memory usage it seems as if Rushmore fails completely and Fox retrieves the entire table, even though SYS(3054) still claims that Rushore is working.
Has anyone else had a problem with SET ANSI ON and large tables?
Nick