Create date.sql

Author: erjan

pgexercises/date.sql

@@ -0,0 +1,66 @@
+select  timestamp '2012-08-31 01:00:00'
+
+
+select timestamp '2012-08-31 01:00:00' - timestamp'2012-07-30 01:00:00' as interval;
+
+
+select generate_series(
+           (date '2012-10-01')::timestamp,
+           (date '2012-10-31')::timestamp,
+           interval '1 day'
+         );
+		 
+		 
+		 
+select extract (day from  date(timestamp '2012-08-31') ) as date_part		 
+
+select extract(epoch from  (timestamp '2012-09-02 00:00:00' - timestamp '2012-08-31 01:00:00'))  as t;
+
+
+select 	extract(month from cal.month) as month,
+	(cal.month + interval '1 month') - cal.month as length
+	from
+	(
+		select generate_series(timestamp '2012-01-01', timestamp '2012-12-01', interval '1 month') as month
+	) cal
+order by month;
+
+
+select (date_trunc('month',ts.testts) + interval '1 month') 
+		- date_trunc('day', ts.testts) as remaining
+	from (select timestamp '2012-02-11 01:00:00' as testts) ts       
+	
+	
+	
+select 
+
+starttime,
+
+starttime + slots* (interval '30 minutes') as endtime
+
+from cd.bookings 
+order by endtime desc ,starttime desc limit 10
+
+
+
+select 
+
+date_trunc('month' , starttime) as month,
+count(facid) 
+from cd.bookings
+group by  date_trunc('month' , starttime)
+order by date_trunc('month' , starttime)
+
+select name, month, 
+	round((100*slots)/
+		cast(
+			25*(cast((month + interval '1 month') as date)
+			- cast (month as date)) as numeric),1) as utilisation
+	from  (
+		select facs.name as name, date_trunc('month', starttime) as month, sum(slots) as slots
+			from cd.bookings bks
+			inner join cd.facilities facs
+				on bks.facid = facs.facid
+			group by facs.facid, month
+	) as inn
+order by name, month