Logical Dataview (LDV) coordination utilizing a temporary field as the coordinating key differs from coordination to a field in another file in both implementation and use. The PARMBLK PARMS macro must have the TMPSYNC keyword set to YES. (See the VISION:Inform Installation Manual).
To implement, the temporary field must be defined in a PROCEDURE. (Refer to the Definition Processor User’s Guide, Section 4.9, Creating Procedures). That PROCEDURE must be included as a component of the LDV. (Refer to the Definition Processor User’s Guide, Section 4.8, Creating Logical Dataviews). Note that a T will be entered under “File” entry preceding the temporary field name on the LDVFILES panel. The PROCEDURE and LDV are promoted with the Definition Processor.
The PROCEDURE is automatically invoked when the LDV is referenced in the VISION:Inform query. Use differs from coordination to database fields in that the PROCEDURE is processed before any statements in the user queries. The temporary field will be built and coordination will take place just once for each master file record. There is never any looping when temporary fields are used for coordination with VISION:Inform.