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 FIELD
 Field (column) definitions
------------------------------------------------------------------------------
 Structure

     typedef struct _FIELD
     {
        USHORT uiType;
        USHORT uiTypeExtended;
        USHORT uiLen;
        USHORT uiDec;
        USHORT uiArea;
        FARP   sym;
     
        struct _FIELD * lpfNext;
     
     } FIELD;
     
     typedef FIELD far * LPFIELD;

 Notes

     The pointer to an array of FIELD structures is contained in the basic
     AREA structure.  Each field is created by a call to the addField()
     method for a given RDD.

 Elements

     uiType

        Contains a literal constant indicating the column's CA-Clipper data
        type.  The numeric constants used to indicate the data types are
        defined in Extend.api and have the following meanings:

        FIELD Data Types
        ---------------------------------------------------------------------
        Constant       Meaning
        ---------------------------------------------------------------------
        CHARACTER      A CA-Clipper character value
        DATE           A CA-Clipper date value
        DOUBLE         A CA-Clipper numeric value stored as an XDOUBLE by the
                       Extend System
        LOGICAL        A CA-Clipper logical value
        MEMO           A CA-Clipper memo value
        NUMERIC        A CA-Clipper numeric value stored as a LONG by the
                       Extend System
        UNDEF          The CA-Clipper NIL value
        ---------------------------------------------------------------------

     uiTypeExtended

        Contains a numeric value indicating a user-defined column type.  This
        member is used to provide support for column types not supported by
        CA-Clipper's default database (.dbf) file format.  The intrinsically
        supported column types are character, numeric, date, logical, and
        memo.  A non-zero value in this field indicates that the column type
        is not one of the intrinsically supported types.  This allows the RDD
        to support column types that are not intrinsically understood by
        CA-Clipper.  Extended types must be translated into CA-Clipper types
        by the RDD and uiTypeExtended values are defined by the RDD.

     uiLen

        Contains a numeric value representing the overall length of the
        column.  RDDs supporting floating point column types should include
        the decimal point in this value.  By convention, variable length
        columns should store a zero (0) in this element.

     uiDec

        Contains a numeric value indicating the number of places to the right
        of the decimal point.  This element is only meaningful when the
        column is a floating point value.

     uiArea

        Contains a numeric value indicating the work area in which the field
        resides.  The CA-Clipper runtime system uses this field to reference
        the appropriate work area.

     sym

        Contains a character data type value representing the column and
        work area to the runtime system.  The CA-Clipper runtime system will
        interpret runtime requests (get or set actions) to this symbol as a
        call to the your driver.

     lpfNext

        Reserved.

 Files  Header file is Rdd.api.

 Used By    AREA


See Also: AREA
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