C5_ORDKEYCOUNT

 ORDKEYCOUNT()
 Return the number of keys in an order
------------------------------------------------------------------------------
 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.

See Also: ORDKEYGOTO() ORDKEYNO() ORDSCOPE()



C5 Index Commands and Functions

Index Commands and Functions

Commands :

DELETE TAG :

Delete a Tag

DELETE TAG <cOrderName> [IN <xcOrderBagName>]
    [, <cOrderName> [IN xcOrderBagName] list>]

INDEX ON … :

Create an index file

INDEX ON <expKey>
    [TAG <cOrderName>]
    TO <xcOrderBagName>
    [FOR <lCondition>] [ALL]
    [WHILE <lCondition>]
    [NEXT <nNumber>]
    [RECORD <nRecord>]
    [REST]
    [EVAL <bBlock>
    [EVERY <nInterval>]
    [UNIQUE]
    [ASCENDING|DESCENDING]

REINDEX :

Rebuild open indexes in the current workarea

REINDEX
    [EVAL <lCondition>]
    [EVERY <nRecords>]]

SET INDEX

Open index file(s) in the current work area

SET INDEX TO [<xcIndex list>]

SET ORDER

Set a new controlling index

SET ORDER TO [<nOrder> | [TAG <cOrderName>]
    [IN <xcOrderBagName>]]>

SET UNIQUE* : 

Toggle the inclusion of nonunique keys into an index

SET UNIQUE on | OFF | <xlToggle>

Functions :

DBCLEARINDEX() :

Close all indexes for the current work area

DBCLEARINDEX() --> NIL

DBCREATEINDEX() :

Create an index file

DBCREATEINDEX( <cIndexName>, <cKeyExpr>,
    <bKeyExpr>, 
    [<lUnique>] ) --> NIL

DBREINDEX() : 

Recreate all active indexes for the current work area

DBREINDEX() --> NIL

DBSEEK() : 

Move to the record having the specified key value

DBSEEK( <expKey>, [<lSoftSeek>] ) --> lFound

DBSETINDEX() : 

Open an index for the current work area

 DBSETINDEX( <cIndexName> ) --> NIL
 DBSETINDEX( <cOrderBagName> ) --> NIL

DBSETORDER() : 

Set the controlling order for the current work area

DBSETORDER( <nOrderNum> ) --> NIL

DESCEND() : 

Return a descending index key value

DESCEND( <exp> ) --> ValueInverted

FOUND() : 

Determine if the previous search operation succeeded

FOUND() --> lSuccess

INDEXEXT() : 

Return the default index extension

INDEXEXT() --> cExtension

INDEXKEY() : 

Return the key expression of a specified index

INDEXKEY( <nOrder> ) --> cKeyExp

INDEXORD() : 

Return the order position of the controlling index

INDEXORD() --> nOrder

ORDBAGEXT() :

Return the default Order Bag RDD extension

ORDBAGEXT() --> cBagExt

ORDBAGNAME() :

Return the Order Bag name of a specific Order

ORDBAGNAME(<nOrder> | <cOrderName>) --> cOrderBagName

ORDCOND()

Specify conditions for ordering

ORDCOND([FOR <lCondition>]
             [ALL] [WHILE <;lCondition>]
             [EVAL <bBlock> [EVERY <nInterval>]]
             [RECORD <nRecord>] [NEXT <nNumber>]
             [REST] [DESCENDING])

ORDCONDSET()

Set the condition and scope for an order

     ORDCONDSET([<cForCondition>],
        [<bForCondition>],
        [<lAll>],
        [<bWhileCondition>],
        [<bEval>],
        [<nInterval>],
        [<nStart>],
        [<nNext>],
        [<nRecord>],
        [<lRest>],
        [<lDescend>],
        [<lAdditive>],
        [<lCurrent>],
        [<lCustom>],
        [<lNoOptimize>]) --> lSuccess

ORDCREATE():

Create an Order in an Order Bag

ORDCREATE(<cOrderBagName>,[<cOrderName>], <cExpKey>,

    [<bExpKey>], [<lUnique>]) --> NIL

ORDDESCEND()

Return and optionally change the descending flag of an order

ORDDESCEND([<cOrder> | <nPosition>],[<cIndexFile>],
            [<lNewDescend>]) --> lCurrentDescend

ORDDESTROY() :

Remove a specified Order from an Order Bag

ORDDESTROY(<cOrderName> [, <cOrderBagName> ]) --> NIL

ORDFOR() :

Return the FOR expression of an Order

ORDFOR(<cOrderName> | <nOrder>
    [, <cOrderBagName>]) --> cForExp

ORDISUNIQUE()

          Return the status of the unique flag for a given order

    ORDISUNIQUE([<cOrder> | <nPosition>],
        [<cIndexFile>]) --> lUnique

ORDKEY() :

Return the Key expression of an Order

ORDKEY(<cOrderName> | <nOrder>
 [, <cOrderBagName>]) --> cExpKey

ORDKEYADD()

Add a key to a custom built order

         ORDKEYADD([<cOrder> | <nPosition>],
            [<cIndexFile>],[<expKeyValue>]) --> lSuccess

 

ORDKEYCOUNT()

Return the number of keys in an order

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

ORDKEYDEL()

Delete a key from a custom built order

        ORDKEYDEL([<cOrder> | <nPosition>],
            [<cIndexFile>],
            [<expKeyValue>]) --> lSuccess

ORDKEYGOTO()

Move to a record specified by its logical record number

ORDKEYGOTO(<nKeyNo>) --> lSuccess

ORDKEYNO()

 Get the logical record number of the current record

         ORDKEYNO([<cOrder> | <nPosition>],
             [<cIndexFile>]) --> nKeyNo

 ORDKEYVAL()

Get key value of the current record from controlling order

ORDKEYVAL() --> xKeyValue

 

ORDLISTADD() :

Add Order Bag contents or single Order to the Order List

ORDLISTADD(<cOrderBagName>
    [, <cOrderName>]) --> NIL

ORDLISTCLEAR() :

Clear the current Order List

ORDLISTCLEAR() --> NIL

ORDLISTREBUILD() :

Rebuild all Orders in the Order List of the current work area

ORDLISTREBUILD() --> NIL

ORDNAME() :

Return the name of an Order in the work area

ORDNAME(<nOrder>[,<cOrderBagName>])
    --> cOrderName

ORDNUMBER() :

Return the position of an Order in the current Order List

ORDNUMBER(<cOrderName>[, <cOrderBagName>]) --> nOrderNo

 ORDSCOPE()

Set or clear the boundaries for scoping key values

ORDSCOPE(<nScope>, [<expNewValue>]) --> uCurrentValue

ORDSETFOCUS() :

Set focus to an Order in an Order List

ORDSETFOCUS([<cOrderName> | <nOrder>]
    [,<cOrderBagName>]) --> cPrevOrderNameInFocus

ORDSETRELAT()

Relate a specified work area to the current work area

    ORDSETRELATION(<nArea> | <cAlias>,<bKey>, [<cKey>])

             --> NIL

ORDSKIPUNIQUE()

Move record pointer to the next or previous unique key

ORDSKIPUNIQUE([<nDirection>]) –> lSuccess