797 ?— 10308 to 1.797 ?— 10308 15 8 bytes
Single ??“3.4 ?— 1038 to 3.4 ?— 1038 7 4 bytes
Replication ID N/A N/A 16 bytes
Decimal 1??“28 precision 15 8 bytes
Many errors are caused by choosing the wrong numeric type for number fields. For instance,
notice that the maximum value for the Integer data type is 32,767. We once saw a database that
ran perfectly for several years and then started crashing with overflow errors. It turned out that the
overflow was caused by a particular field being set to the Integer data type, and when the company
occasionally processed very large orders, the 32,767 maximum was exceeded.
It is best to design your tables very conservatively and allow for larger values than you ever expect
to see in your database. This is not to say that it is a good idea to use the Double data type for all
numeric fields. The Double data type is very large (8 bytes) and is quite slow when used in calculations
for another numeric operation. Instead, the Single data type is probably best for most
floating-point calculations, and the Long Integer is best for most data where decimal points are
irrelevant.
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