select
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SQL Study3 - SELECTDB/SQL 2018. 8. 7. 09:40
-- 46. 사원수가 가장 많은 도시에서 근무하는 모든 사원들의 부서별 및-- 직무별 평균 연봉을 조회하라.SELECT L.CITY , D.DEPARTMENT_NAME , J.JOB_ID , ROUND(AVG(E.SALARY) , 0) AVG_SALARYFROM EMPLOYEES E , DEPARTMENTS D , LOCATIONS L , JOBS J , ( SELECT * FROM ( SELECT L.CITY , COUNT(1) CNT FROM EMPLOYEES E , DEPARTMENTS D , LOCATIONS L WHERE E.DEPARTMENT_ID = D.DEPARTMENT_ID AND D.LOCATION_ID = L.LOCATION_ID GROUP BY L.CITY ORDER BY CNT D..
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SQL Study2 - SELECTDB/SQL 2018. 8. 6. 14:54
-- 1. 모든 사원의 이름(FIRST_NAME, LAST_NAME)을 조회하라. SELECT FIRST_NAME , LAST_NAMEFROM EMPLOYEES; -- 2. 모든 사원의 모든 정보를 조회하라.SELECT *FROM EMPLOYEES; -- 3. 모든 도시 명을 조회하라.SELECT CITYFROM LOCATIONS; -- 4. 이름(FIRST_NAME)이 M 으로 시작하는 사원의 모든 정보를 조회하라.SELECT *FROM EMPLOYEESWHERE FIRST_NAME LIKE 'M%'; -- 5. 이름(FIRST_NAME)의 두 번째 글자가 'a'인 사원의 이름(FIRST_NAME)과 연봉을 조회하라.SELECT FIRST_NAME , SALARYFROM EMPLOYEESWHERE FI..
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SQL - SELECTDB/SQL 2018. 8. 1. 17:24
SELECT FIRST_NAME , LAST_NAMEFROM EMPLOYEES; SELECT *FROM EMPLOYEES; SELECT CITYFROM LOCATIONS; SELECT DEPARTMENT_NAMEFROM DEPARTMENTS; SELECT COUNTRY_ID , COUNTRY_NAMEFROM COUNTRIES; SELECT DISTINCT MANAGER_ID , FIRST_NAMEFROM EMPLOYEESORDER BY MANAGER_ID DESC; SELECT *FROM EMPLOYEESORDER BY EMPLOYEE_ID ASC; SELECT *FROM EMPLOYEESORDER BY SALARY DESC; SELECT *FROM EMPLOYEESORDER BY HIRE_DATE AS..