목록Oracle (2)

기록이 힘이다.

[SQL 쿡북] 13. 계층적 쿼리

13.1 상위-하위 관계 표현하기 select a.ename || ' works for ' || b.ename as emps_and_mgrs from emp a, emp b where a.mgr = b.empno select concat(a.ename, ' works for ',b.ename) as emps_and_mgrs from emp a, emp b where a.mgr = b.empno select a.ename + ' works for ' + b.ename as emps_and_mgrs from emp a, emp b where a.mgr = b.empno -------------------------------------------------------------------- ..
SQL 2023. 5. 2. 07:00
[SQL 쿡북] 12 보고서 작성과 재구성하기

12.1 결과셋을 하나의 행으로 피벗하기 select sum(case when deptno=10 then 1 else 0 end) as deptno_10, sum(case when deptno=20 then 1 else 0 end) as deptno_20, sum(case when deptno=30 then 1 else 0 end) as deptno_30 from emp select deptno, case when deptno=10 then 1 else 0 end as deptno_10, case when deptno=20 then 1 else 0 end as deptno_20, case when deptno=30 then 1 else 0 end as deptno_30 from emp order by 1..
SQL 2023. 4. 27. 07:10
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