[RESOLVED] select command

[vang]

hi,
i have 2 columns of data:
- column 1 contains the name of child parents
- column 2 contains the name of the child

I would like to display the names of those parents which their names also appear in column 2. Eg.

parent | child

albert | susan
susan | peter
Alvin | Kevin
Joe | susan

In the above example, the correct result is susan.

May i know how to construct the mysql command to achieve this? thanks.

[Lars_Berg]

select parent from t where parent in (select child from t)

[vang]

thank you 🙂