Library /sys$common/syshlp/CDDLHELP.HLB  —  DEFAULT_VALUE
  The DEFAULT_VALUE field attribute clause sets a default value  for  a
  field accessed by VAX DATATRIEVE.

1  –  Parameters

  fixed_point_number

  dtrdv_quoted_string

       A VAX DATATRIEVE expression that is the default value.

2  –  Syntax Rules

   o  The quoted string (dtrdv_quoted_string)  or  fixed  point  number
      must  be  a  valid  VAX DATATRIEVE expression.  However, the CDDL
      compiler  does  not  check  for  correct  syntax.   It  is   your
      responsibility to provide a correct default value expression.

   o  You can use 8-bit characters in CDDL quoted strings.

3  –  Usage Notes

   o  The DEFAULT_VALUE clause, used with VAX DATATRIEVE,  serves  much
      the   same   purpose  as  the  INITIAL_VALUE  clause.   The  main
      difference is that the INITIAL_VALUE clause assigns a value to  a
      field when the field is first allocated, usually at compile time,
      but the DEFAULT_VALUE clause assigns a value to a field each time
      the record is stored without an explicit value assigned to it.

   o  Only VAX DATATRIEVE supports  the  DEFAULT_VALUE  clause.   Other
      language processors ignore it.

4  –  Example

  The following example assigns a  DEFAULT_VALUE  of  0  to  the  field
  TOTAL_PRICE.

  TOTAL_PRICE             DATATYPE IS VIRTUAL FIELD
                          COMPUTED BY DATATRIEVE AS
                              "UNIT_PRICE * QUANTITY"
                          DEFAULT_VALUE FOR DATATRIEVE IS 0.
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