Set a selective relation from this window to the child window, or actually from the server of this window to the server of the other window. A selective relation is one that limits operations on the child server to those records that match the relation condition.

Namespace: VO
Assembly: VOGUIClasses (in VOGUIClasses.dll) Version: 2.19

Syntax

Copy

 VIRTUAL METHOD SetSelectiveRelation(
	oDWChild,
	uRelation,
	cRelation
) AS USUAL CLIPPER

[ClipperCallingConventionAttribute(new string[] { ... })]
public virtual Usual SetSelectiveRelation(
	Usual oDWChild = default,
	Usual uRelation = default,
	Usual cRelation = default
)

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Parameters

oDWChild (Optional): Type: Usual
The window attached to the child server; which must be a data window linked to a server of compatible type. If omitted, all relations for this server are removed (although the recommended way of doing this is the DataWindow:ClearRelations() method).
uRelation (Optional): Type: Usual
The relation code block for the server, The name or symbol representing the field from this server; a code block is constructed and macro-compiled or the array of field names or symbols representing the relation for the server. The field names are concatenated with plus signs and formed into a code block which is macro-compiled.
cRelation (Optional): Type: Usual
When the relation is specified as a code block, a string version of the code block can be provided as well; it is returned by the Relation() method.

Return Value

Type: Usual
TRUE if successful; otherwise, FALSE.

Remarks

Tip
This operation may not be supported, depending on whether the servers used supports relations and are of compatible types.

Examples

The API can take these forms:

Copy

1oDWCustomer:SetSelectiveRelation(oDWOrders, {||_FIELD->CustNo},"CustNo")
2oDWCustomer:SetSelectiveRelation(oDWOrders, #CustNo)
3oDWCustomer:SetSelectiveRelation(oDWOrders, {#LastName,#Initial,#FirstName})

Reference

DataWindow Class

VO Namespace