Click or drag to resize

OrderSpec Class

X#
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: 2.19
Syntax
 CLASS OrderSpec
Request Example View Source

The OrderSpec type exposes the following members.

Constructors
  NameDescription
Public methodCode exampleOrderSpec
Instantiates an OrderSpec object using an existing DBFileSpec object.
Top
Properties
  NameDescription
Public propertyAdd
A logical value specifying whether open orders should remain open while the new order is being created.
Public propertyAll
A logical value determining whether the record scope is for all records in the DBF (TRUE)
Public propertyAutoOpen
Determines if this index file will open when the DBF file is opened.
Public propertyAutoOrder
Determines if this index file will set the first order when it is opened.
Public propertyAutoShare
Determines if this index file will be opened in the same share mode as the DBF file.
Public propertyCurrent
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.
Public propertyCustom
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.
Public propertyDBF
The DBFileSpec object with which this OrderSpec object is associated.
Public propertyDescend
A logical value determining if this is to be a descending order. Defaults to FALSE for ascending order.
Public propertyEvalBlock
The code block to be evaluated based upon OrderSpec:Interval. The code block should return a TRUE value.
Public propertyFileName
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.
Public propertyForBlock
The FOR condition code block to build this order.
Public propertyForCond
The FOR condition string used to build this order.
Public propertyHPLock
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.
Public propertyInterval
An integer determining the interval for the execution of OrderSpec:EvalBlock during order building.
Public propertyIsCond
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.
Public propertyKeyInfo
The 1-D, 4-element array containing the structure of the OrderSpec object.
Public propertyLockOffSet
The current NTX locking offset as a numeric value.
Public propertyNoOptimize
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.
Public propertyOrderBlock
The code block of the index key expression used to create this order.
Public propertyOrderExpr
The string of the index key expression used to create this order.
Public propertyOrderName
The order (tag) name for this order. Used for creating multi-order order files (bags).
Public propertyRecno
The individual record number to be processed. Defaults to zero (0) for all records.
Public propertyRecords
The number of records to be processed starting from OrderSpec:Start.
Public propertyRest
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.
Public propertyStart
Determines the starting record number from which to start building this order.
Public propertyStrictRead
A logical value determining whether the records will be read directly from disk during order creation.
Public propertyUnique
A logical value determining whether this order is to be a unique order (no duplicate keys).
Public propertyWhileBlock
A WHILE condition code block used during the building of this order.
Top
Methods
  NameDescription
Public methodCode exampleOrderAdd
Adds order information from an existing index file to the OrderSpec object and associates this OrderSpec object with the DBFileSpec object used for instantiation.
Public methodCode exampleOrderCreate
Create new orders, and if empty, fills in OrderSpec information and associates the created order with the DBFileSpec object.
Public methodCode exampleOrderDelete
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.
See Also

Reference