Page 779 - ExtendSim User Guide
P. 779

The Relationship dialog
If there is existing data in a child field, this dialog opens and allows you to arbitrate what happens when the relationship is made. If there is no existing data, the dialog does not open. The options are:
• Link and match existing data in Child field to a record in the Parent field. If existing data in the child matches data in the parent, the data is left unchanged. Otherwise, it is cleared and the record is left blank so the value can be manu- ally selected.
Data Management and Exchange 753
ExtendSim databases for internal data storage
Parent Child relationship dialog
• ClearallcurrentChilddata.Thisoptionclearsalltheexistingdatainthechild.
Linking a database to data
Databases are used to store data for use in the model or to store model outputs. A model can access a database’s information by dynamically linking to it, by using data access and equa- tion-based blocks, and through ModL programming.
The following section discusses how to dynamically link a dialog item to a database. Using Read and Write blocks to access database data is described below.
Dynamic data linking
The steps for dynamically linking a block’s dialog item to an ExtendSim database table are:
1) CreateanExtendSimdatabase(see“ExtendSimdatabasesforinternaldatastorage”on page 747.)
2) Linkaparameterordatatable,asillustratedin“Dynamiclinkingtointernaldatastruc- tures” on page 737.
How To

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