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Data conversion issues
If, in spite of your best efforts, it becomes necessary to change the data type of a field containing
data, you may suffer data loss as the data-type conversion occurs. You should be aware of the
effects of a data-type conversion on existing data:
n Any data type to AutoNumber: Can??™t be done. The AutoNumber field type must be created
fresh in a new field.
n Text to Number, Currency, Date/Time, or Yes/No: In most cases, the conversion will be
made without damaging the data. Inappropriate values are automatically deleted. For
instance, a text field containing ???January 28, 2007??? will be faithfully converted to a
Date/Time field. If, however, you change a field containing ???January 28, 2007??? to a
Yes/No data type, its value will be deleted.
n Memo to Text: A straightforward conversion with no loss or corruption of data. Any text
longer than the field size specified for the Text field is truncated and lost.
n Number to Text: No loss of information. The number value is converted to text using the
General Number format.


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