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Data.DB.TAutoIncField

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Data.DB.TIntegerFieldData.DB.TNumericFieldData.DB.TFieldSystem.Classes.TComponentSystem.Classes.TPersistentSystem.TObjectTAutoIncField

Delphi

TAutoIncField = class(TIntegerField)

C++

class PASCALIMPLEMENTATION TAutoIncField : public TIntegerField

Properties

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

Description

TAutoIncField is a persistent field object for an autoincrement field in a dataset.

TAutoIncField provides access to an autoincrement field in a table. Autoincrement fields can hold values in the range -2,147,483,648 to 2,147,483,647, and are used as a counter for the records in the dataset. Each record is given a unique value in an autoincrement field, with each record receiving the next highest integer from that of the previously inserted record. Autoincrement 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 autoincrement field (with or without a TAutoIncField 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 runtime. When using dynamic field components, you can access the TAutoIncField instance using the dataset's Fields property or FieldByName method.

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