Datatypes for each datastructure field (data type of the column) must be same. If multiple datatypes used for a single column then the following error will be generated.
VisualSim.kernel.util.IllegalActionException:
Problem with data types in same column, column type (double), row type (String)
Error_Number : DB_003
Possible_Solution : Check in column: MyDbl
Description : Database block supports single column type, detected two types
in .Database_invalid_Datatype.Upper Database
at VisualSim.actor.lib.Database.preinitialize(Unknown Source)
at VisualSim.actor.Director.preinitialize(Unknown Source)
at VisualSim.simulators.de.kernel.DEDirector.preinitialize(Unknown Source)
at VisualSim.actor.CompositeActor.preinitialize(Unknown Source)
at VisualSim.actor.Manager.preinitializeAndResolveTypes(Unknown Source)
at VisualSim.actor.Manager.initialize(Unknown Source)
at VisualSim.actor.Manager.execute(Unknown Source)
at VisualSim.actor.Manager.run(Unknown Source)
at java.lang.Thread.run(Thread.java:745)
at VisualSim.kernel.util.VisualSimThread.run(Unknown Source)
Solution: Datatype for each column entries must be same.