kurs:correlated_subquery
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kurs:correlated_subquery [2009/09/24 16:12] mh |
kurs:correlated_subquery [2020/06/02 09:26] admin |
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| + | <code> | ||
| + | select first_name, last_name, e.employee_id, c from employees e, | ||
| + | (select employee_id, count(employee_id) c from job_history | ||
| + | group by employee_id | ||
| + | having count(employee_id) >= 2) g | ||
| + | where e.employee_id = g.employee_id | ||
| + | select first_name, last_name, employee_id from employees e | ||
| + | where (select count(*) from job_history where employee_id = e.employee_id) >= 2 | ||
| + | |||
| + | |||
| + | select first_name, last_name from employees e where | ||
| + | -- employee_id in (select manager_id from employees where e.employee_id = manager_id) | ||
| + | exists (select 1 from employees where e.employee_id = manager_id) | ||
| + | </code> | ||
| + | |||
| + | <code> | ||
| + | select first_name, last_name, e.employee_id, c from employees e, | ||
| + | (select employee_id, count(employee_id) c from job_history | ||
| + | group by employee_id | ||
| + | having count(employee_id) >= 2) g | ||
| + | where e.employee_id = g.employee_id | ||
| + | |||
| + | select first_name, last_name, employee_id from employees e | ||
| + | where (select count(*) from job_history where employee_id = e.employee_id) >= 2 | ||
| + | </code> | ||
| + | |||
| + | <code> | ||
| + | select * from ( | ||
| + | SELECT tst_fahrzeuge.fhz_name, count(tst_extras.ext_name) c | ||
| + | FROM tst_extras, tst_fahrzeuge, tst_fhz_ext_int | ||
| + | WHERE ( (tst_extras.ext_id = tst_fhz_ext_int.fei_ext_id) | ||
| + | AND (tst_fahrzeuge.fhz_id = tst_fhz_ext_int.fei_fhz_id) | ||
| + | ) | ||
| + | group by fhz_name | ||
| + | ) where c > 1 | ||
| + | |||
| + | |||
| + | select fhz_name from tst_fahrzeuge outer | ||
| + | where ( | ||
| + | SELECT count(ext_name) c | ||
| + | FROM tst_extras, tst_fahrzeuge inner, tst_fhz_ext_int | ||
| + | WHERE ( (ext_id = fei_ext_id) | ||
| + | AND (inner.fhz_id = fei_fhz_id) | ||
| + | and outer.fhz_name = inner.fhz_name | ||
| + | )) > 1 | ||
| + | </code> | ||
| + | |||
| + | <code> | ||
| + | with emp_per_country as ( | ||
| + | SELECT dep.department_id, | ||
| + | department_name, | ||
| + | cou.country_id, | ||
| + | country_name, | ||
| + | COUNT(employee_id) c | ||
| + | FROM hr.employees emp | ||
| + | JOIN hr.departments dep | ||
| + | ON emp.department_id = dep.department_id | ||
| + | JOIN hr.locations loc | ||
| + | ON loc.location_id = dep.location_id | ||
| + | JOIN hr.countries cou | ||
| + | ON cou.country_id = loc.country_id | ||
| + | GROUP BY dep.department_id, department_name, cou.country_id, country_name | ||
| + | ORDER BY COUNT(employee_id) DESC | ||
| + | ) | ||
| + | select country_name, department_name, c from emp_per_country o | ||
| + | where c = (select max(c) from emp_per_country where country_id = o.country_id) | ||
| + | </code> | ||
kurs/correlated_subquery.txt ยท Last modified: 2022/03/15 10:39 by admin
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