ORDKEYCOUNT()
 Return the number of keys in an order
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 Syntax

     ORDKEYCOUNT([<cOrder> | <nPosition>],
        [<cIndexFile>]) --> nKeys

 Arguments

     <cOrder> | <nPosition> is the name of the order or a number
     representing its position in the order list.  Using the order name is
     the preferred method since the position may be difficult to determine
     using multiple-order index files.  If omitted or NIL, the controlling
     order is assumed.

     Specifying an invalid order will raise a runtime error.

     <cIndexFile> is the name of an index file, including an optional
     drive and directory (no extension should be specified).  Use this
     argument with <cOrder> to remove ambiguity when there are two or more
     orders with the same name in different index files.

     If <cIndexFile> is not open by the current process, a runtime error is
     raised.

 Returns

     ORDKEYCOUNT() returns the number of keys in the specified order.

 Description

     ORDKEYCOUNT() counts the keys in the specified order and returns the
     result as a numeric value.  If the order is not conditional and no scope
     has been set for it, ORDKEYCOUNT() is identical to RECCOUNT(), returning
     the number of records in the database file.  However, for a conditional
     order, there may be fewer keys than there are records, since some
     records may not meet the order's for condition or may not fall inside
     the scope specified by ORDSCOPE()--in counting the keys, ORDKEYCOUNT()
     respects the currently defined scope and for condition.

     By default, this function operates on the currently selected work area.
     It will operate on an unselected work area if you specify it as part of
     an aliased expression.

 Examples

     .  This example demonstrates using ORDKEYCOUNT() with various
        orders:

        USE customer
        // Assume 1000 total records,
        // 500 less than thirty years old, and
        // 895 making less than 50,000

        INDEX ON Age TO Age

        INDEX ON First TO First FOR Age < 30
        INDEX ON Last TO Last FOR Salary < 50000

        // Age is the controlling order
        SET INDEX TO Age, First, Last

        ? RECCOUNT()                     // Result: 1000
        ? ORDKEYCOUNT()                  // Result: 1000

        ? ORDKEYCOUNT("First")         // Result: 500
        ? ORDKEYCOUNT(3)               // Result: 895

 Files   Library is CLIPPER.LIB.