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TUnsignedAutoIncField = class(TLongWordField)


class PASCALIMPLEMENTATION TUnsignedAutoIncField : public TLongWordField


Type Visibility Source Unit Parent
class public
Data.DB Data.DB


TUnsignedAutoIncField is a persistent field object for an auto-increment unsigned integer value field in a dataset.

TUnsignedAutoIncField provides access to an auto-increment field in a table. Auto-increment fields can hold values in the range from 0 through 4,294,967,295, and are used as a counter for the records in the dataset. Each record is given a unique value in an auto-increment field, with each record receiving the next highest integer from that of the previously inserted record. Auto-increment fields are commonly used to provide a unique primary key value for a record.

Note: Auto-incrementing fields are a function of the database back-end. An application should not attempt to set a field value for an auto-increment field (with or without a TUnsignedAutoIncField object).

If you use the Fields editor at design time to create a persistent field component for the auto-incrementing field, you can access it by name at run time. When using dynamic field components, you can access the TUnsignedAutoIncField instance using the dataset's Fields property or FieldByName method.

See Also