OrderSpec Class

OrderSpec class was designed to model index information at the order level - not file level - and complement the DBFileSpec class.

Inheritance Hierarchy

Object
OrderSpec

Namespace: VO
Assembly: VORDDClasses (in VORDDClasses.dll) Version: 2.21

Syntax

Copy

 CLASS OrderSpec

public class OrderSpec

Request Example View Source

The OrderSpec type exposes the following members.

Constructors

	Name	Description
	OrderSpec	Instantiates an OrderSpec object using an existing DBFileSpec object.

Top

Properties

	Name	Description
	Add	A logical value specifying whether open orders should remain open while the new order is being created.
	All	A logical value determining whether the record scope is for all records in the DBF (TRUE)
	AutoOpen	Determines if this index file will open when the DBF file is opened.
	AutoOrder	Determines if this index file will set the first order when it is opened.
	AutoShare	Determines if this index file will be opened in the same share mode as the DBF file.
	Current	A logical value determining whether only those records in the controlling order and in the scope are included in this order. Defaults to FALSE so that all records in DBF are included.
	Custom	A logical value determining if this is to be a custom order. Valid for RDDs that support custom orders. Defaults to FALSE for a non-custom order.
	DBF	The DBFileSpec object with which this OrderSpec object is associated.
	Descend	A logical value determining if this is to be a descending order. Defaults to FALSE for ascending order.
	EvalBlock	The code block to be evaluated based upon OrderSpec:Interval. The code block should return a TRUE value.
	FileName	The drive, path and file name of the order. The drive and path default to either the current window's drive and path or to the drive and path used in SetDefault(), if omitted.
	ForBlock	The FOR condition code block to build this order.
	ForCond	The FOR condition string used to build this order.
	HPLock	A logical value determining whether the DBFNTX RDD will use the HPLocking scheme for building this order. The default is FALSE, i.e., no HPLocking.
	Interval	An integer determining the interval for the execution of OrderSpec:EvalBlock during order building.
	IsCond	A logical value indicating whether this is a conditional order. This is assigned TRUE internally when any of the conditional ASSIGNs are assigned values and is not required to be assigned manually to create a conditional order.
	KeyInfo	The 1-D, 4-element array containing the structure of the OrderSpec object.
	LockOffSet	The current NTX locking offset as a numeric value.
	NoOptimize	A logical value determining whether the FOR condition used to build this order should be optimized. Valid for RDDs that support query optimizations. Defaults to FALSE for no optimization.
	OrderBlock	The code block of the index key expression used to create this order.
	OrderExpr	The string of the index key expression used to create this order.
	OrderName	The order (tag) name for this order. Used for creating multi-order order files (bags).
	Recno	The individual record number to be processed. Defaults to zero (0) for all records.
	Records	The number of records to be processed starting from OrderSpec:Start.
	Rest	A logical value indicating that records are to be processed starting from OrderSpec:Start (TRUE). Defaults to FALSE to process all records from the beginning of file.
	Start	Determines the starting record number from which to start building this order.
	StrictRead	A logical value determining whether the records will be read directly from disk during order creation.
	Unique	A logical value determining whether this order is to be a unique order (no duplicate keys).
	WhileBlock	A WHILE condition code block used during the building of this order.

Top

Methods

	Name	Description
	OrderAdd	Adds order information from an existing index file to the OrderSpec object and associates this OrderSpec object with the DBFileSpec object used for instantiation.
	OrderCreate	Create new orders, and if empty, fills in OrderSpec information and associates the created order with the DBFileSpec object.
	OrderDelete	Deletes orders from a multi-order file or a physical index file of a single-order file. NULLs out OrderSpec object information in the OrderSpec object and the DBFileSpec object specific to this order.

Top

Remarks

Instantiation requires a DBFileSpec object. Each order will require a separate OrderSpec object. For single-order index formats such as DBFNTX, this is equivalent to one OrderSpec object per physical file. For multi-order index formats such as DBFCDX, this would mean multiple OrderSpec objects for one physical file. For more information on the conditional index order instance variables, refer to the OrdCondSet() function.

Reference

VO Namespace