With the help of a simple custom function you can filter record based on individual character entered in search field.
Length ( Text ) > 1 ;
CharacterStack( Left ( Text ; Length ( Text ) - 1 ) ) & "" & Text; Text
So, you need to define a simple auto enter text calculation field where it will calculate the character stack value of destination field
and use that field in your portal relationship where you are going to filter value.
Suppose you have a list of Names in Contact table and you want to filter Names by enter value in a global field zgt_Name.
First of all define a field like “NameStack_calc” in destination table from where you want to display value and used that field in relationship as
zgc_Name (Filter Global field of Source table) = NameStack_calc (Destination table)
Destination Field Caculation:
NameStack_calc (Destination table) = If ( not IsEmpty ( Trim ( Name )) ; CharacterStack ( Name ) & “” & “BLANK” ; “BLANK” )
Source Field Calculation:
zgc_Name ( Source table) = If ( not IsEmpty ( Trim ( zgt_Name ) ) ; zgt_Name ; “BLANK” )
Here I have used the BLANK for display all the names when nothing is entered in filter global field (zgt_Name).