小白求解关于两张表PL/SQL累加求和怎么写？

Question

org_code ,dep_code ,batch_code from a
budget_amt from b

org_code dep_code batch_code budget_amt amount
400 T 10010 100 100
400 T 10010 200 300
400 T 10010 300 600
401 201 10002 50 50
401 201 10002 70 120
401 201 10002 100 220

        这个显示amount通过budget_amt累加的SQL应该怎么写才能显示出来呢？
        （org_code ,dep_code ,batch_code属于a表），（budget_amt）属于b表

Answer 1

select a.org_code ,a.dep_code ,a.batch_code, sum(b.budget_amt) as amount  from a,b
on a.org_code = b.org_code
GROUP BY a.org_code