根据查出主外键关联并组装sql
select a.constraint_name,
a.table_name,
' update ' || a.table_name || ' set ' || b.column_name ||
' = 900000200 WHERE ' || b.column_name || ' = 700000142;' updateSql
from user_constraints a, user_cons_columns b
where a.constraint_type = 'R'
and a.r_constraint_name = 'PK_T_PRDT_CT'
and a.constraint_name = b.constraint_name;