Example
select cst.constraint_schema, cst.constraint_name,
fk.table_name, fk.ordinal_position, fk.column_name,
pk.table_name, pk.column_name
from qsys2.syscst cst join qsys2.syskeycst fk
on fk.constraint_schema = cst.constraint_schema
and fk.constraint_name = cst.constraint_name
join qsys2.sysrefcst ref
on ref.constraint_schema = cst.constraint_schema
and ref.constraint_name = cst.constraint_name
join qsys2.syskeycst pk
on pk.constraint_schema = ref.unique_constraint_schema
and pk.constraint_name = ref.unique_constraint_name
where cst.constraint_type = 'FOREIGN KEY'
and fk.ordinal_position = pk.ordinal_position
and pk.table_name = 'PRIMARYTABLE'
and pk.column_name = 'EMPID'
order by cst.constraint_schema, cst.constraint_name
