CO09: Is a condition seasonal, alergies for example

Returns the distribution of condition occurrence per season in the northern hemisphere, defined in the following way:
 Spring  March 21 - June 21
 Summer  June 22 - September 22
 Fall  September 23 - December 21
 Winter  December 22 - March 20

 Parameter  Example  Mandatory  Notes
condition_concept_id 31967 Yes Condition concept identifier for 'Nausea'

Sample query run:
The following is a sample run of the query. The input parameters are highlighted in blue
SELECT season, 
       COUNT(*)as season_freq
 SELECT CASE WHEN (daymonth>0320 AND daymonth<=0621) THEN 'Spring'
	     WHEN (daymonth>0621 AND daymonth<=0922) THEN 'Summer'
	     WHEN (daymonth>0922 AND daymonth<=1221) THEN 'Fall'
	     WHEN (daymonth>1221 OR  (daymonth>0000 AND daymonth<=0520)) THEN 'Winter'
        ELSE 'Unknown' end AS season
    SELECT cast(substring(condition_start_date from 6 for 2)||
           substring(condition_start_date from 9 for 2) as int) AS daymonth,condition_start_date
    FROM   condition_occurrence
    WHERE  condition_concept_id = 31967
 ) AS condition_season
GROUP BY season
ORDER BY season_freq
Output field list:
 Field  Description
season Season as defined in the northern hemisphere.
season_freq Frequency of condition occurrence in the season.

Sample output record:
 Field  Description
season Summer
season_freq 62924