Oracle面试题2

----插入数据

 1    insert into test_a values(1,‘a‘,‘bei‘,2230,‘11-2月-2001‘);
 2    insert into test_a values(2,‘b‘,‘jing‘,2231,‘11-2月-2002‘);
 3    insert into test_a values(3,‘c‘,‘shang‘,2232,‘11-3月-2002‘);
 4    insert into test_a values(4,‘c‘,‘hai‘,2233,‘13-3月-2002‘);
 5    insert into test_a values(5,‘d‘,‘guang‘,2234,‘12-2月-2001‘);
 6    commit;
 7 
 8    insert into test_b values(‘c‘,‘shen‘,2240);
 9    insert into test_b values(‘d‘,‘shen‘,2241);
10    commit;--提交
11    select * from test_a;--查询数据
12    truncate table test_a;--删除数据

1. 将表A中的字段LOGDATE中为2001-02-11的数据更新为2003-01-01，请写出相应的SQL语句（该字段类型为日期类型）

   1 update test_a 
   2 set logdate = to_date(‘2003-01-01‘,‘yyyy-MM-dd‘) 
   3 where logdate = to_date(‘2001-02-11‘,‘yyyy-MM-dd‘);
   4 commit;
   5 select * from test_a;--查询数据

2. 请写出将表中NAME存在重复的记录都列出来的SQL语句（按NAME排序）

   1 select * from (
   2        select a.name 
   3        from test_a a 
   4        group by a.name 
   5        having count(*)>1 
   6        order by name);

3. 请写出题目2中，只保留重复记录的第一条，删除其余记录的SQL语句（即使表中不存在重复记录）

    1 delete test_a a 
    2 where a.name <> (
    3   select * from (
    4    select a.name 
    5    from test_a a 
    6    group by a.name 
    7    having count(*)>1 
    8    order by name));
    9    commit;
   10    select * from test_a;--查询数据

4. 请写出将B表中的ADDRESS,PHONE更新到A表中的SQL语句（按NAME相同进行关联）

    1 update test_a a
    2 set a.address = decode((select distinct b.address 
    3                 from test_b b 
    4                 where a.name = b.name),null,a.address,(select distinct b.address 
    5                 from test_b b 
    6                 where a.name = b.name))
    7    ,a.phone = decode((select distinct b2.phone 
    8                 from test_b b2 
    9                 where a.name = b2.name),null,a.phone,(select distinct b2.phone 
   10                 from test_b b2 
   11                 where a.name = b2.name));
   12     commit;--提交
   13     select * from test_a;--查询数据

5. 请写出将A表中第3-5行数据列出来的SQL语句

   1 select b.id,b.name,b.address,b.phone,b.logdate
   2 from (select rownum rn,id,name,address,phone,logdate 
   3     from test_a) b 
   4 where b.rn between 3 and 5;

-------------------------欢迎建议更优秀的代码

Oracle面试题2

标签：