SQL server query for selecting data with 5 seconds interval -


can tell me t-sql script selecting data interval of 5 seconds? have scada system logs data parameter every second want retrieve data interval of 5 sec, start time decided user. example if start = 10:00:01 , end 11:00:00 want see data @ 10:00:06, 10:00:11, 10:00:16... not data @ 10:00:02, 10:00:03 10:00:05, , between 10:00:07 , 10:00:10

i first create dummy data every second 10:00 10:16

declare @data table(creation datetime2); declare @start datetime = '20150930 10:00:00'; declare @end datetime;  -- create dummy data 10:00:00 10:16:40 ids(n) (     select row_number() over(order n) (         select 1 (values(1), (1), (1), (1), (1), (1), (1), (1), (1), (1)) x1(n)         cross join (values(1), (1), (1), (1), (1), (1), (1), (1), (1), (1)) x2(n)         cross join (values(1), (1), (1), (1), (1), (1), (1), (1), (1), (1)) x3(n)     ) x(n) ) insert @data(creation) select dateadd(second, n, @start) ids

i calculate difference in second between start date , creation date , use modulo 5 (%5) in order find date every 5s:

set @start = '20150930 10:01:03' set @end = '20150930 10:05:00';  select *     , datediff(second, creation, @start)     , datediff(second, creation, @start) % 5 @data (datediff(second, creation, @start) % 5) = 0     , creation >= @start , creation <= @end

output:

creation                    datediff  modulo    (no column name) 2015-09-30 10:01:03.0000000 0         0 2015-09-30 10:01:08.0000000 -5        0 2015-09-30 10:01:13.0000000 -10       0 ...                         ...       ...

you can see datediff n*5 , there modulo = 0


Comments

Post a Comment

Popular posts from this blog

html - Outlook 2010 Anchor (url/address/link) -

i'm trying link specific pdf page msoutlook'10 or msword'10, #page=... anchor particularly useful , works fine elsewhere. unfortunately when click [ctr-k] in outlook or winword, links re-formatted assuming unc path. pdf file located on shared drive. using "file:" prefix links open pdf in adobe reader (outside of browser), , "http:" open inside browser. issue seem need open in browser "file:" prefix in order anchor work. know anchors work inside browser. outlook uses windows/explorer default program (based on file extension) seems open in adobe reader neglecting anchor. is aware of solution, link specific page or bookmark of shared-pdf ms outlook and/or winword link? common references: mailermailer.com/...anchor-tags-html-emails campaignmonitor.com/...anchor-links-in-email-newsletters/ stackoverflow.com/...anchor-in-pdf-document
Read more

javascript - Why does running this loop 9 times take 100x longer than running it 8 times? -

consider code: test = function() { } t = new test(); (var = 0; < 8; i++) { result = t instanceof test; } if change number of iterations 8 9 , loop take 100 times longer complete in latest version of firefox (41.0.1). tested on 2 different pcs , magic limit 8. here jsperf test used: http://jsperf.com/instanceof-8-times-vs-9-times does have idea why might happen? seems specific instanceof . not happen if else object, example check property. note: filed bugzilla bug this. jan de mooij mozilla team has posted details in bugzilla thread . here's simplistic interpretation of highly technical answers: in i < 8 case, firefox smart enough hoist result = t instanceof test; statement out of loop (according tests, doesn't seem omit altogether). in i < 9 case, apparently doesn't optimization . why? reason not clear, related fact 9 iterations threshold above function considered "hot" enough run through jit compiler. i < 8 cas...
Read more

Getting gateway time-out Rails app with Nginx + Puma running on Digital Ocean -

following this guide setup app on digital ocean droplet, not working. site not loading , it's throwing: "gateway time-out". the puma server works, since ps aux | grep puma prints: root 15878 0.0 0.4 376832 2168 ? sl 12:50 0:00 puma 2.13.4 (unix:///var/www/myapp/shared/tmp/sockets/myapp-puma.sock) [20150930164940] root 15881 0.0 0.7 903676 3692 ? sl 12:50 0:06 puma: cluster worker 0: 15878 [20150930164940] root 24654 0.0 0.1 11748 916 pts/2 s+ 18:00 0:00 grep --color=auto puma my nginx config: user root; worker_processes 1; events { worker_connections 1024; } http { upstream puma { server unix:///var/www/myapp/shared/tmp/sockets/myapp-puma.sock; } server { listen 80; server_name myapp.com; root /var/www/myapp/current/public; access_log /var/www/myapp/current/log/access.log; error_log /...
Read more