Yes, using an autoincrement field will make it impossible to use it in VFP6 (VFP7 and older versions).

>I have a database on Visual Foxpro 6.0. If I open it with Visual Foxpro 8 and add a table with the autoincrement field will that affect me accessing the data from Visual foxpro 6.0? I know the autoincrement feature is not available in 6 and that's fine I just want to make sure that I'm still able to access and work with the database in 6.
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>Thanks.