SQL Clauses - WHERE, GROUP BY, HAVING, ORDER BY | Functions - COUNT() , DISTINCT() - Day12

Опубликовано: 05 Июнь 2026
на канале: Learn with RD

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SELECT DEPARTMENT_ID,COUNT(*) FROM EMPLOYEES GROUP BY DEPARTMENT_ID;

SELECT DEPARTMENT_ID,COUNT(*) FROM EMPLOYEES GROUP BY DEPARTMENT_ID HAVING COUNT(*) = 1;

SELECT DEPARTMENT_ID,JOB_ID FROM EMPLOYEES ORDER BY DEPARTMENT_ID DESC;

SELECT * FROM EMPLOYEES;

SELECT SALARY,COUNT(*) FROM EMPLOYEES GROUP BY SALARY ORDER BY COUNT(*);

SELECT SALARY,COUNT(*) FROM EMPLOYEES GROUP BY SALARY ORDER BY SALARY,COUNT(*);

SELECT SUBJECT FROM STUDENTS;

INSERT INTO STUDENTS VALUES(100,'SCIENCE',98,'M');

SELECT DISTINCT(SUBJECT) FROM STUDENTS;

SELECT SUBJECT,COUNT(DISTINCT(SUBJECT)) FROM STUDENTS GROUP BY SUBJECT ORDER BY SUBJECT;

SELECT SUBJECT,COUNT(*) FROM STUDENTS GROUP BY SUBJECT HAVING COUNT(*) = 2;