I need to create an inline view that will give me all dates between two specified. Here is the question posed to me that I need to answer: This basic query gets me the last 6 hours of history table entries for an item, grouped into minutes (if an item has a delay of 5 seconds, it takes the max out of each 11 entries per minutes).
set @iid=231; set @hid=1; select from_unixtime(t.clock), DATE_FORMAT(from_unixtime(t.clock),'%j %h:%i %p') as mins, MAX(t.value) as value_max from history t where t.itemid = (select itemid from items where itemid = @iid and hostid = @hid) and DATE_SUB(CURRENT_TIMESTAMP(),INTERVAL 6 HOUR) <= from_unixtime(t.clock) group by mins order by t.clock; It'll fetch 360 entries (360 minutes in 6 hours) that looks like this: from_unixtime(t.clock) mins value_max 2/24/2007 05:56:12 055 05:56 AM 0.29 2/24/2007 05:57:02 055 05:57 AM 0.2 2/24/2007 05:58:02 055 05:58 AM 0.23 2/24/2007 06:01:03 055 06:01 AM 0.02 2/24/2007 06:02:02 055 06:02 AM 0.08 The format you see for mins is DAY_OF_YEAR HOUR:MIN AM/PM. DAY_OF_YEAR is unique, as in 55th day of this year. Okay, so if I can JOIN this table with another table/view/sub query that has EVERY MINUTE of the last 6 hours in a similarly formatted column like 'mins', we should be able to spot the missing 2 minutes. from_unixtime(t.clock) mins value_max 2/24/2007 05:56:12 055 05:56 AM 0.29 2/24/2007 05:57:02 055 05:57 AM 0.2 2/24/2007 05:58:02 055 05:58 AM 0.23 2/24/2007 05:59:02 055 05:59 AM NULL <<-- from the join 2/24/2007 06:00:02 055 06:00 AM NULL <<- from the join 2/24/2007 06:01:03 055 06:01 AM 0.02 2/24/2007 06:02:02 055 06:02 AM 0.08 Bryan Cantwell Director, Development (M) 469.361.1272 [EMAIL PROTECTED] www.FireScope.net
