C5_REPLACE

 REPLACE
 Assign new values to field variables
------------------------------------------------------------------------------
 Syntax

     REPLACE <idField> WITH <exp>
        [, <idField2> WITH <exp2>...]
        [<scope>] [WHILE <lCondition>] [FOR <lCondition>]

 Arguments

     <idField> is the name of the field variable to be assigned a new
     value.  If <idField> is prefaced with an alias, the assignment takes
     place in the designated work area.

     WITH <exp> defines the value to assign to <idField>.

     <scope> is the portion of the current database file to REPLACE.  The
     default is the current record, or NEXT 1.  Specifying a condition
     changes the default to ALL records in the current work area.

     WHILE <lCondition> specifies the set of records meeting the
     condition from the current record until the condition fails.

     FOR <lCondition> specifies the conditional set of records to REPLACE
     within the given scope.

 Description

     REPLACE is a database command that assigns new values to the contents of
     one or more field variables in the current record in the specified work
     areas.  The target field variables can be character, date, logical,
     memo, or numeric.  REPLACE performs the same function as the assignment
     operator (:=) except that it assumes that an unaliased reference is to a
     field variable.  This means that you can assign new values to field
     variables using assignment statements provided that the field variable
     references are prefaced with an alias, the FIELD alias, or declared
     using the FIELD declaration statement.

     The default scope of REPLACE is the current record unless a scope or
     condition is specified.  If a scope or condition is specified, the
     replace operation is performed on each record matching the scope and/or
     condition.

     Warning!  When you REPLACE a key field, the index is updated and the
     relative position of the record pointer within the index is changed.
     This means that REPLACEing a key field with a scope or a condition may
     yield an erroneous result.  To update a key field, SET ORDER TO 0 before
     the REPLACE.  This ensures that the record pointer moves sequentially in
     natural order.  All open indexes, however, are updated if the key field
     is REPLACEd.

     In a network environment, REPLACEing the current record requires an
     RLOCK().  REPLACEing with a scope and/or condition requires an FLOCK()
     or EXCLUSIVE USE of the current database file.  If a field is being
     REPLACEd in another work area by specifying its alias, that record must
     also be locked with an RLOCK().  Refer to the "Network Programming"
     chapter in the Programming and Utilities Guide for more information.

 Examples

     .  This example shows a simple use of REPLACE:

        USE Customer NEW
        APPEND BLANK
        USE Invoices NEW
        APPEND BLANK
        //
        REPLACE Charges WITH Customer->Markup * Cost,;
           Custid WITH Customer->Custid,;
           Customer->TranDate WITH DATE()

     .  This example uses assignment statements in place of the
        REPLACE command:

        FIELD->Charges := Customer->Markup * FIELD->Cost
        FIELD->Custid := Customer->Custid
        Customer->TranDate := DATE()

 Files   Library is CLIPPER.LIB.

See Also: COMMIT FLOCK() RLOCK()

 

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4 responses to “C5_REPLACE

  1. Pingback: C5_UPDATE | Viva Clipper !

  2. Pingback: C5_STORE | Viva Clipper !

  3. Pingback: DB Commands | Viva Clipper !

  4. Pingback: C5 Commands | Viva Clipper !

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