create table test (name char(10), i1 integer, i2 integer);

insert into test values ('홍길동',  1000, 1500);
insert into test values ('홍길동',  1100, 1700);
insert into test values ('홍길동',  1800, 1900);
insert into test values ('강감찬',  0900, 1000);
insert into test values ('이순신',  1000, 1400);

select NAME, MIN(I1), MAX(I2) from TEST GROup by name;

NAME        MIN(I1)     MAX(I2)    
----------------------------------------
홍길동      1000        1900       
강감찬      900         1000       
이순신      1000        1400       
3 rows selected.

이걸 말씀하시는건지요??

제가 원하는 답은

홍길동 1000  1700

홍길동 1800   1900

강참찬 900    1000

이순신 1000   1400

입니다.

즉 홍길동이 1100부터 1500까지 중복되어 있고

이를 제거하고 자료를 뽑아내고자 합니다.

고수님의 고견을 기다리며...

SELECT
       A.NAME,
       A.START_SEQ,
       A.END_SEQ
  FROM TEST_SQL A,
       (SELECT
               NAME,
               MIN(START_SEQ) AS START_SEQ
          FROM TEST_SQL
         GROUP BY NAME ) B
 WHERE A.NAME = B.NAME
   AND A.START_SEQ = B.START_SEQ
UNION
SELECT
       A.NAME,
       A.START_SEQ,
       A.END_SEQ
  FROM TEST_SQL A,
       (SELECT
               NAME,
               MAX(END_SEQ) AS END_SEQ
          FROM TEST_SQL
         GROUP BY NAME ) B
 WHERE A.NAME = B.NAME
   AND A.END_SEQ = B.END_SEQ

좀 무식해 보이는건가 ;;;

select name "name", min(i1) "start", i2 "end"
from (select x.name, x.i1, (select max(y.i2)
                                        from "test" y
                                        where x.name = y.name
                                           and x.i2 between y.i1 and y.i2)
         from "test" x) as z(name, i1, i2)
group by name, i2;

=== <Result of SELECT Command in Line 13> ===

  name                        start          end
================================================
  '강감찬    '                  900         1000
  '이순신    '                 1000         1400
  '홍길동    '                 1000         1700
  '홍길동    '                 1800         1900

4 rows selected.

오호~