How to set the listbox 'Selection Attribute' when the source aggregate has one column

The documentation says to add a boolean but I can't seem to do that to an aggregate that has one column which is the single group by of one column.  My aggregate is over a table that has many different cities. I would normally in SQL do a select distinct but I am doing a group by of just the city to get a list of cities. I want to be able to allow multiple selection of different cities but don't know what this selection Attribute has. The docs say to add a boolean attribute but I can't seem to do that to an aggregate that has a single group by column.

Thanks

Solution

Hi Bradford,

You will need to create another list of records with the same columns of the aggregate plus the one for the selected. and assign the aggregate to that list.

Regards,

Marcelo


Solution

Marcelo, Thank you for your response.

Allow me to clarify what I had to do for your verification.

Added a New Entity with matching field type of the unique code from my aggregate and a boolean named Selected.
Added a local variable of the new entity type.
Added an assign after the aggregate that assigned the aggregate list to the local variable and verified the Mapping was correct for the one unique field.
Added a ListBox and set the source to the new local variable.
This allowed me to be able to set the Selection Attribute to the the additional feild in the new entity.

Thanks again.

Hi Bradford,

You don't need to add a new entity. You can use a structure. 

The rest looks fine.

Regards,

Marcelo