Return the number of keys in an order.
XSharp.RT (in XSharp.RT.dll) Version: 2.3b
Syntax View Source
uOrder AS USUAL,
cIndexFile AS USUAL
) AS USUAL
public static Usual OrdKeyCount(
[DefaultParameterValueAttribute(0, 1)] Usual uOrder,
[DefaultParameterValueAttribute(0, 1)] Usual cIndexFile
- Type: Usual
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.
- Type: Usual
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.
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 can be made to operate on an unselected work area by specifying it within an aliased expression
If there is no order in operation, the return value will be 0 and not the value of RecCount().
This example demonstrates using OrdKeyCount() with various orders.
7INDEX ON Age TO Age
8INDEX ON First TO First FOR Age < 30
9INDEX ON Last TO Last FOR Salary < 50000
11SET INDEX TO Age, First, Last