if Column1 (table1)=Column1(table2), Column1)-

[Qlikuser09]

Display column1 if the column 1 of table 1 fields equals column 1 of table 2 . Both the tables are linked by a primary key.

[stevejoyce]

maybe this?  =Concat(Distinct field1, ',') = Concat(distinct field2, ',')

(field 1 is column1 from table 1, field 2 is column 1 from table 2)