Re: pgsql-function - Mailing list pgsql-sql

From hubert depesz lubaczewski
Subject Re: pgsql-function
Date
Msg-id 20150414173946.GA20194@depesz.com
Whole thread Raw
In response to pgsql-function  (Rishi Ranjan <rishiranjan706@gmail.com>)
Responses Re: pgsql-function  ("David G. Johnston" <david.g.johnston@gmail.com>)
List pgsql-sql
On Tue, Apr 14, 2015 at 03:39:38AM -0700, Rishi Ranjan wrote:
> i have data like below and where ap_key is same for two different
> first_occurence column . here i need to write a function which can
> calculate the difference of two timestamp values for a Ap_Key and then with
> difference it should multiply the severity
> 
> AAA_key   AP_KEY   FIRSTOCCURRENCE   SEVERITY
>       111      418    3/4/2014 0:00         5
>       111      418    3/4/2014 0:05         0
>       112       12    3/4/2014 0:40         4
>       112       12    3/4/2014 0:45         0
>       113       13    3/4/2014 1:05         3
>       113       13    3/4/2014 1:10         0
>       114      114    3/4/2014 1:30         2
>       114      114    3/4/2014 1:35         0
>       115       35    3/4/2014 2:10         1
>       115       35    3/4/2014 2:15         0
>       116      116   3/4/2014 10:14         4
>       116      116   3/4/2014 10:19         0
>       117      127   3/4/2014 11:45         3
>       117      127   3/4/2014 11:49         0
>       118      118   3/4/2014 12:10         2
>       118      118   3/4/2014 12:14         0
>       119       19   3/4/2014 12:35         1
>       119       19   3/4/2014 12:39         0
>       119      120    3/4/2014 0:00         4
>       119      120    3/4/2014 1:40         0

Given this data, why don't you simply:

select   AAA_key,   AP_KEY,   max(SEVERITY),   max(FIRSTOCCURRENCE) - min(FIRSTOCCURRENCE)
from   table
group by   AAA_key,   AP_KEY;

and then do whatever math you need on severity or FIRSTOCCURRENCE
differences.

depesz



pgsql-sql by date:

Previous
From: "David G. Johnston"
Date:
Subject: Re: pgsql-function
Next
From: "David G. Johnston"
Date:
Subject: Re: pgsql-function