Shulou(Shulou.com)06/01 Report--

Syntax:

Select grouping function, column (required to appear after group by)

From table

Where..

List of group by groups

Order by...

# case: query the average salary of each department

SELECT AVG (salary), department_idFROM employeesGROUP BY department_idORDER BY department_id DESC

# case: query the maximum wage for each type of job

SELECT MAX (salary), job_idFROM employeesGROUP BY job_id

# case: query the number of locations in each department

SELECT COUNT (location_id), department_nameFROM departmentsGROUP BY department_name

# case: query the average salary of each department that contains a character in the mailbox

SELECT AVG (salary), department_idFROM employeesWHERE email LIKE ('% a%') GROUP BY department_id

# case: inquire about the maximum salary of each leader with bonus

SELECT MAX (salary), manager_idFROM employeesWHERE commission_pct IS NOT NULLGROUP BY manager_id

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