It sounds like either A) you are trying to copy data from one table to another or B) you want to select the data for one table from the choices available in another.
In response to A, why store two copies of the same data? There's no reason to do that. In response to B, use a combo box.
In response to A, why store two copies of the same data? There's no reason to do that. In response to B, use a combo box.
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