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  1. #1
    Steven Guest

    How to update the database?

    I have two tables:
    emp(employee_no, ename, job, manager_no, hiredate, sal, comm, deptno)
    dept(deptno, dname, location)
    The manager_no is the manager who manage that employee, and manager is also
    a employee in the emp table.

    Q. How can I give all managers a commission(comm) equal to 10% of the sum
    of salaries of employees they directly manage. Update the emp table accordingly.

    Q. How can I add a new column No_Of_Emp to the dept table, and store in it
    the number of employees in the corresponding department by using update.


  2. #2
    Michael Levy Guest

    Re: How to update the database?

    Welcome to the world of hierarchies! SQL (the language) does not handle them

    I've got a couple of resources that you should check out:
    Joe Celko's SQL For Smarties book; Ben-Gan had an article in SQL Server Mag.
    that discussed handling hierarchies like this; and David Rozenshtein et al,
    put together a little booked called Tree Processing in SQL.

    Michael Levy MCDBA, MCSD, MCT

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