SQL exercises on employee Database: Check whether all the employees numbers are indeed unique
SQL employee Database: Exercise-103 with Solution
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103. Write a query in SQL to check whether all the employees numbers are indeed unique.
Sample table: employees
SELECT emp_id, count(*) FROM employees GROUP BY emp_id;
emp_id | count --------+------- 69324 | 1 69062 | 1 63679 | 1 67858 | 1 66564 | 1 64989 | 1 67832 | 1 65646 | 1 68319 | 1 68454 | 1 66928 | 1 65271 | 1 68736 | 1 69000 | 1 (14 rows)
Sample Database: employee
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Previous: Write a query in SQL to list the name of departments where atleast 2 employees are working in that department.
Next: Write a query in SQL to list the no. of employees and average salary within each department for each job name.
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