Should a reference table include numeric PK identity column value of 0? <p>We have a table that contains the valid currency codes. We are choosing to use a numeric value as the primary key rather than a 3 char ISO Currency code, for example. </p> <p>General consensus has concluded that this <code>CurrencyId</code> column should contain values that begin with zero. Since the US dollar is the primary currency for us, it claimed the first position with a value of 0.</p> <p>My thought is that identity columns should not start at zero for the sole reason that some languages initialize numerics to zero and as a result the currency code may be unintentionally set to <code>USD</code> when really it was never assigned.</p> <p>Am I all wet? I would prefer to assign a <code>CurrencyId</code> of 1 to <code>USD</code>.</p>