Mapping data from different context data variables into the same prop

Normally you would want to do a "Concatenation" rule, rather than a straight up overwrite...

I assume that you would have a specified format? 

Something like:

changeType_context_source_tabType_origin

or 

changeType|context|source|tabType|origin

Then there is the possibility of whether or not you have a placeholder like "na" when no value is available, or if the item is left out completely:

changeType_context_source_na_origin

or

changeType_context_source_origin

And those rules will need slightly different behaviour... but the basics would be:

Overwrite the value of Event Context (p46) (Prop46) with Concatenated Value Delimiter _

     change_type(Context Data)

     context(Context Data)

     source(Context Data)

     tabtype(Context Data)

     origin(Context Data)

Or, if you need to build in the possibility of optional values. Believe it or not, having "na" placeholders is easier, here would be a way to do that:

Overwrite the value of Event Context (p46) (Prop46) with Concatenated Value Delimiter (leave blank)

     change_type(Context Data)

     (Condition) If change_type(Context Data) is set

Overwrite the value of Event Context (p46) (Prop46) with Concatenated Value Delimiter (leave blank)

     Custom Value na

     (Condition) If change_type(Context Data) is not set

Overwrite the value of Event Context (p46) (Prop46) with Concatenated Value Delimiter (leave blank)

    Event Context (p46) (Prop46)

    Custom Value _

    context(Context Data)

    (Condition) If context(Context Data) is set

Overwrite the value of Event Context (p46) (Prop46) with Concatenated Value Delimiter (leave blank)

    Event Context (p46) (Prop46)

    Custom Value _

    Custom Value na

    (Condition) If context(Context Data) is not set

Overwrite the value of Event Context (p46) (Prop46) with Concatenated Value Delimiter (leave blank)

    Event Context (p46) (Prop46)

    Custom Value _

    source(Context Data)

    (Condition) If source(Context Data) is set

Overwrite the value of Event Context (p46) (Prop46) with Concatenated Value Delimiter (leave blank)

    Event Context (p46) (Prop46)

    Custom Value _

    Custom Value na

    (Condition) If source(Context Data) is not set

Overwrite the value of Event Context (p46) (Prop46) with Concatenated Value Delimiter (leave blank)

    Event Context (p46) (Prop46)

    Custom Value _

    tabtype(Context Data)

    (Condition) If tabtype(Context Data) is set

Overwrite the value of Event Context (p46) (Prop46) with Concatenated Value Delimiter (leave blank)

    Event Context (p46) (Prop46)

    Custom Value _

    Custom Value na

    (Condition) If tabtype(Context Data) is not set

Overwrite the value of Event Context (p46) (Prop46) with Concatenated Value Delimiter (leave blank)

    Event Context (p46) (Prop46)

    Custom Value _

    origin(Context Data)

    (Condition) If origin(Context Data) is set

Overwrite the value of Event Context (p46) (Prop46) with Concatenated Value Delimiter (leave blank)

    Event Context (p46) (Prop46)

    Custom Value _

    Custom Value na

    (Condition) If origin(Context Data) is not set

Basically, for each item, you create a rule to use the context variable IF it exists, and to use "na" if it doesn't exist... then just keep concatenating values onto your prop...

If you don't have placeholders, that one can get tricky... only because of those set delimiters... you actually have to use different rules as you need 2 conditions... one to check if there is a value already in prop46 (to know whether or not to add an _ before adding the context variable), and one to know if you have a value in the context variable to add anything at all....

Unfortunately, at each Action level, you can only add one condition... if we could have multiple it would be similar to above... but with no placeholders, you can do a simple overwrite with change_type(Context Data)

Then you need to have another rule that checks if the next context variable exist (context(Context Data)), if it does, then you need two actions.. one that checks if Prop46 is set to know IF to concatenate the _ and then a simple concatenate for the context variable... (you can concatenate empty prop46 with the context... so only the _ action requires a condition:

Main Condition - IF context(Context Data) is set

Overwrite the value of Event Context (p46) (Prop46) with Concatenated Value Delimiter (leave blank)

    Event Context (p46) (Prop46)

    Custom Value _

    (Condition) If Event Context (p46) (Prop46) is set

Overwrite the value of Event Context (p46) (Prop46) with Concatenated Value Delimiter (leave blank)

    Event Context (p46) (Prop46)

    context(Context Data)

Make rules for each context variable...

This will prevent you from ending up with your prop starting / ending with, or having multiple delimiters in a row

_value__value2_

But I suspect you want either placeholders, or those delimiters for easier classification rules... but it's good to show you that you can do that, if that is your final goal