Oracle-diary/QUERY
||와 DISTINCT
reallygeorge?
2020. 1. 30. 17:56
| 14:57:11 SQL> SELECT ENAME || ' IS A ' || JOB <- 원화 특수문자 SHIFT를 해주면 ||가 되는데 각각의 열을 이어준다. |
| 14:57:15 2 FROM EMP; |
| ENAME||'ISA'||JOB |
| ------------------------- |
| SMITH IS A CLERK <-이어진 모습 |
| ALLEN IS A SALESMAN |
| WARD IS A SALESMAN |
| JONES IS A MANAGER |
| MARTIN IS A SALESMAN |
| BLAKE IS A MANAGER |
| CLARK IS A MANAGER |
| SCOTT IS A ANALYST |
| KING IS A PRESIDENT |
| TURNER IS A SALESMAN |
| ADAMS IS A CLERK |
| ENAME||'ISA'||JOB |
| ------------------------- |
| JAMES IS A CLERK |
| FORD IS A ANALYST |
| MILLER IS A CLERK |
| 14 개의 행이 선택되었습니다. |
| 14:58:57 SQL> SELECT ENAME || ' IS A ' || JOB "별칭" |
| 14:59:39 2 FROM EMP ; |
| 별칭 |
| ------------------------- |
| SMITH IS A CLERK |
| ALLEN IS A SALESMAN |
| WARD IS A SALESMAN |
| JONES IS A MANAGER |
| MARTIN IS A SALESMAN |
| BLAKE IS A MANAGER |
| CLARK IS A MANAGER |
| SCOTT IS A ANALYST |
| KING IS A PRESIDENT |
| TURNER IS A SALESMAN |
| ADAMS IS A CLERK |
| 별칭 |
| ------------------------- |
| JAMES IS A CLERK |
| FORD IS A ANALYST |
| MILLER IS A CLERK |
| 15:12:33 SQL> SELECT DISTINCT DEPTNO(부서번호) <- DISTINCT는 중복된 것을 제거한다 . |
| 15:13:31 2 FROM EMP |
| 15:13:32 3 ; |
| DEPTNO |
| ---------- |
| 30 |
| 20 |
| 10 |