Differences

This shows you the differences between two versions of the page.

--- kurs:group_by_beispiele [2010/10/28 15:27]
mh created
+++ kurs:group_by_beispiele [2014/05/20 15:24]
mh
@@ Line 1: / Line 1: @@
+<code>
+with ym as (
+select employee_id,
+    --   extract(year from hire_date) y,
+       extract(month from hire_date) m
+       from employees
+)
+select m, count(employee_id)
+  from ym
+       group by m
+       order by m
+</code>
+<code>
+with gehaltklassen as (
+select salary, case when salary < 7000 then 0
+            when salary < 12000 then 1
+            else 2 end gehaltklasse
+from employees
+)
+select gehaltklasse, dg, count(dg) from (
+   select gehaltklasse, decode(gehaltklasse,
+, 'wenig',
+, 'mittel',
+, 'viel') dg
+     from gehaltklassen )
+group by gehaltklasse, dg
+order by gehaltklasse
+</code>
 <code>

dokuwiki