Show all relationships between two columns in MySQL

I have a single table that has data like the following:

Column 1 -- Column 2

A -- Z

A -- Y

B -- Y

I am looking for a way in MySQL to roll up this data so that I get the following table that will show group associations:

Column 1 -- Column 2

A,B -- Z,Y

I can use the group_concat function to get one column at a time grouped together, b开发者_如何学Gout I need both columns to be grouped to show the relationships. Any advice is greatly appreciated!

Try INFORMATION_SCHEMA.TABLE_CONSTRAINTS and INFORMATION_SCHEMA.KEY_COLUMN_USAGE. Reference : http://dev.mysql.com/doc/refman/5.0/en/key-column-usage-table.html

This will work.

select * from INFORMATION_SCHEMA.TABLE_CONSTRAINTS;