Use UpdateMode property to specify the criteria for locating a record in the database when posting updates. The default value is upWhereKeyOnly. 

UpdateMode specifies whether records are located using all columns (fields), on only the key fields, or on the key fields plus the original values of fields that have been modified. To control how AnyDAC locates records by specifying individual fields, use the field components' ProviderFlags property.

property UpdateMode: TUpdateMode;

Unique Identifying Fields, Update Command Generation, TField.ProviderFlags, TADBottomUpdateOptions.KeyFields