Diagram 6: Introduce a "Path" Column

• Substitute "path" column for "name" column

• Join row's name and all of its ancestors' names with a pipe (|)

        "path","nationality","gender","age","income"
        "|Alpha","","","",""
        "|Alpha|Epsilon","","","",""
        "|Alpha|Epsilon|Kappa","","","",""
        "|Alpha|Zeta","","","",""
        "|Alpha|Zeta|Lambda","","","",""
        "|Alpha|Zeta|Mu","","","",""
        "|Beta","","","",""
        "|Beta|Eta","","","",""
        "|Beta|Theta","","","",""
        "|Gamma","","","",""
        "|Gamma|Iota","","","",""
        "|Gamma|Iota|Delta","","","",""
        "|Delta","","","",""