When opening a database do I have to select the whole table?

This works:
strSQL = “SELECT * FROM mytable”
rstdb.open strSQL, dbcon, , , adcmbtable

This Does Not:
strSQL = “SELECT * FROM mytable WHERE myfiled LIKE ‘ABC*’”
rstdb.open strSQL, dbcon, , , adcmbtable

I tested the statement in the Visual Data Manager and it works fine. Can this just not be done?