Question

This query is something about connecting between two ids in just one table.

Table: employer

Employee no.  Lastname  Firstname  reports to  title
111           Garret    Mike       333         sales manager
333           Frank     Savage     444         President

My question is how do I connect this table?

The table should be like:

Employee no.  Lastname  Firstname  reports to(Supervisor No.)  Firstname   Lastame
111           Garret    Mike       333                         Frank       Savage

I tried:

Select Employee no., Lastname, Firstname, reports to AS SuperVisorNumber, firstname, lastname From Employer
Where Employer.reports to =Employeeno.reports to

This is just an example. Don’t worry about the misspelling and everything.

Answer 1

You will need to join the table to itself:

select e1.Employeeno,
  e1.lastname EmpLastName,
  e1.firstname empFirstName,
  e1.reportsto,
  e2.firstname MgrFirstName,
  e2.lastname MgrLastName
from employer e1
inner join employer e2
  on e1.reportsto = e2.employeeno

See SQL Fiddle with Demo

If you want to see all employees, including the president, then change it to a LEFT JOIN:

select e1.Employeeno,
  e1.lastname EmpLastName,
  e1.firstname empFirstName,
  e1.reportsto,
  e2.firstname MgrFirstName,
  e2.lastname MgrLastName
from employer e1
left join employer e2
  on e1.reportsto = e2.employeeno

See SQL Fiddle with Demo

If, you want to use more descriptive table aliases, then you can use something like this:

from employer employee
left join employer manager
  on employee.reportsto = manager.employeeno