一道与时间差有关的SQL面试题

题目:

一组通话记录(总共500万条):
ID 主叫号码 被叫号码 通话起始时间 通话结束时间 通话时长
1 98290000 0215466546656 2007-02-01 09:49:53.000 2007-02-01 09:50:16.000 23
2 98290000 021546654666 2007-02-01 09:50:29.000 2007-02-01 09:50:41.000 12
3 98290000 021546654666 2007-02-01 09:50:58.000 2007-02-01 09:51:12.000 14
4 68290900 0755133329866 2007-02-01 10:04:31.000 2007-02-01 10:07:13.000 162
5 78290000 0755255708638 2007-02-01 10:48:26.000 2007-02-01 10:49:23.000 57
6 78290000 0755821119109 2007-02-01 10:49:39.000 2007-02-01 10:52:55.000 196
7 78290000 035730928370 2007-02-01 11:30:45.000 2007-02-01 11:31:58.000 73
8 78290000 0871138889904 2007-02-01 11:33:47.000 2007-02-01 11:35:00.000 73
9 68290000 035730928379 2007-02-01 11:52:20.000 2007-02-01 11:54:56.000 156
10 68290000 0298521811199 2007-02-01 12:44:45.000 2007-02-01 12:45:04.000 19

求其中同一个号码的两次通话之间间隔大于10秒的通话记录ID
例如:6,7,8,9,10条记录均符合。

create table phone (

id number,

zph number,

bph number,

pbegin date,

pend date

);

insert into phone values(1,98290000,0215466546656,to_date('2007-02-01 09:49:53','YYYY-MM-DD HH24:MI:SS'),to_date('2007-02-01 09:50:16','YYYY-MM-DD HH24:MI:SS'));

insert into phone values(2,98290000,021546654666,to_date('2007-02-01 09:50:29','YYYY-MM-DD HH24:MI:SS'),to_date('2007-02-01 09:50:41','YYYY-MM-DD HH24:MI:SS'));

insert into phone values(3,98290000,021546654666,to_date('2007-02-01 09:50:58','YYYY-MM-DD HH24:MI:SS'),to_date('2007-02-01 09:51:12','YYYY-MM-DD HH24:MI:SS'));

insert into phone values(4,68290900,0755133329866,to_date('2007-02-01 10:04:31','YYYY-MM-DD HH24:MI:SS'),to_date('2007-02-01 10:07:13','YYYY-MM-DD HH24:MI:SS'));

insert into phone values(5,78290000,0755255708638,to_date('2007-02-01 10:48:26','YYYY-MM-DD HH24:MI:SS'),to_date('2007-02-01 10:49:23','YYYY-MM-DD HH24:MI:SS'));

insert into phone values(6,78290000,0755821119109,to_date('2007-02-01 10:49:39','YYYY-MM-DD HH24:MI:SS'),to_date('2007-02-01 10:52:55','YYYY-MM-DD HH24:MI:SS'));

insert into phone values(7,78290000,035730928370,to_date('2007-02-01 11:30:45','YYYY-MM-DD HH24:MI:SS'),to_date('2007-02-01 11:31:58','YYYY-MM-DD HH24:MI:SS'));

insert into phone values(8,78290000,0871138889904,to_date('2007-02-01 11:33:47','YYYY-MM-DD HH24:MI:SS'),to_date('2007-02-01 11:35:00','YYYY-MM-DD HH24:MI:SS'));

insert into phone values(9,68290000,035730928379,to_date('2007-02-01 11:52:20','YYYY-MM-DD HH24:MI:SS'),to_date('2007-02-01 11:54:56','YYYY-MM-DD HH24:MI:SS'));

insert into phone values(10,68290000,0298521811199,to_date('2007-02-01 12:44:45','YYYY-MM-DD HH24:MI:SS'),to_date('2007-02-01 12:45:04','YYYY-MM-DD HH24:MI:SS'));

commit;

SQL> select * from phone;

ID        ZPH        BPH PBEGIN      PEND

---------- ---------- ---------- ----------- -----------

1   98290000 2154665466 2007/2/1 9: 2007/2/1 9:

2   98290000 2154665466 2007/2/1 9: 2007/2/1 9:

3   98290000 2154665466 2007/2/1 9: 2007/2/1 9:

4   68290900 7551333298 2007/2/1 10 2007/2/1 10

5   78290000 7552557086 2007/2/1 10 2007/2/1 10

6   78290000 7558211191 2007/2/1 10 2007/2/1 10

7   78290000 3573092837 2007/2/1 11 2007/2/1 11

8   78290000 8711388899 2007/2/1 11 2007/2/1 11

9   68290000 3573092837 2007/2/1 11 2007/2/1 11

10   68290000 2985218111 2007/2/1 12 2007/2/1 12

10 rows selected

SQL> select t1.id

2    from (select rownum rm, t.* from phone t) t1,

3         (select rownum rm, t.* from phone t) t2

4   where t1.zph = t2.zph

5     and t1.rm = t2.rm + 1

6     and (t1.pbegin - t2.pend)*24*60*60 > 10;

ID

----------

2

3

6

7

8

10

6 rows selected

说明:oracle中date类型数据“+、-”操作返回值单位为“day”。

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