Hi,
We have a CB request field working fine but we would like to display an info string when an empty value is returned.
I don't clearly see where I can add this ?
The set up is 
So when id is empty we'd like to display a message to the user in the dropdown saying "empty" instead of a blank area that they don't know they can click on.

I thought that maybe substitutions in the column value would work and tried to input a string instead of "id" like this :
  'GROUPE_MARKET_COLUMN' => '[cb:if id>0]id[cb:elseif id<=0]Aucun événement[/cb:elseif][/cb:if]'

But it doesn't seem to work.
Can you give me the clue ?

You are right the id is always a number
But as this is a dropdown request, the first area is an empty space if the user does not want to select any value.
I am simply trying to find a solution to put a name in this empty space (something like "no selection" for instance)

I come back quickly on this subject :
The solution works fine to display the label if there is no value.
But when editing the field (ajax or no) and viewing the dropdown list the first value is still empty. Is it possible to fill the first line with an indication ?
In the above example, I use title as the column title. Shouldn't it display Title in the first line ?

EDIT:
On the same field with the same query, I'd also like to display what is stored in params, how can I get this ?
For instance I get the id and the title of a row, and in its params I have : {"drophscat":"50"}
I use this as a group column in the results but would like to display it also.
What is the way to achieve this ? I don't need to store it but only to display it near the title

I tried [label] - [group] in the custom label or the display but it does not work