may know how to have a field which have the join function?:

I'm afraid that your question is a bit ambiguous. If by join you mean to concatenate two text strings, you don't need a funciton, but the & operator:

"Chuck " & "Ross" = "Chuck Ross"

If this isn't what you mean, please provide more information.

Chuck

I just read your other post, and you definately want the & operator.

Say that your two fields are Field_1 and Field_2. Create a third field called Both_Fields or something, and set it to be a calculation with a text result with the following equation:

Field_1 & Field_2

If you want the two fields to be separated by a return, make the equation read as follows:

Field_1 & "