drop-down list with available items only

[barbarascristin]

In my app, I have a table named 'Agendas Disponíveis' that is categorized as 'read-only'. It serves as the data source for a dropdown list in the main table 'Input Dados'. The user selects a value from this list, and I would like that once they make a selection, that option is no longer available in the dropdown for their next response."

[Joseph_Seddik]

Please show the columns configuration of your form's table. 

[barbarascristin]

primary table:

Table in which it is referenced:

Expression to avoid duplicating identical answers in the dropdown list:

My databases consist of 'Available Schedules,' which contains pre-defined schedules for appointments, 'Input Data,' where the data is stored and where 'Available Schedules' is referenced to display the available schedules in a dropdown list, and it should be a unique value. 'Source' is a table referenced in 'Input Data,' showing the origins of each trailer, and 'Carrier' is also a table referenced in 'Input Data,' displayed in a dropdown list, and it's not a unique value.

My problem is that I would like only the schedules that have not been booked to appear in my dropdown list, as they are being selected;

[Joseph_Seddik]

Thanks. Do you have only one slot available per appointment? or can two different users for example book the same schedule? 

[barbarascristin]

One per query, I developed this expression, and apparently, it served me well :))

SELECT(Agendas Disponiveis[Agende aqui sua descarga], NOT(IN([Agende aqui sua descarga], INPUT DADOS [Agende aqui sua descarga])))

[Joseph_Seddik · Accepted solution]

You can use:

Agendas Disponiveis[Agende aqui sua descarga]
- INPUT DADOS[Agende aqui sua descarga]