SQL Query: Getting Data by Age Groups from a date column

Recently i was working on a Ballot progress reporting system at my office. for that i have to generate a data set which has number of voters grouped by age group. This can be easily done at application level coding. But i wanted to have SQL query which directly out put these data for me as a SP.

Voting data is collected to this table

 

So here is what my query looks like.


SELECT ages.age_s +Sep.s+ages.age_e as AgeGroup ,COUNT(T)as Count
FROM (SELECT ' - ' AS s) AS Sep
CROSS JOIN
(SELECT '18' AS age_s, '24' AS age_e
UNION ALL
SELECT '25' AS age_s, '34' AS age_e
UNION ALL
SELECT '35' AS age_s, '44' AS age_e
UNION ALL
SELECT '45' AS age_s, '54' AS age_e
UNION ALL
SELECT '55' AS age_s, '64' AS age_e
UNION ALL
SELECT '65' AS age_s, '74' AS age_e
UNION ALL
SELECT '75' AS age_s, '100' AS age_e) AS ages
LEFT OUTER JOIN 
(SELECT ((DATEPART(year, CONVERT (date, GETDATE())
))-(DATEPART(year, dob))) as T from VotingInfo ) AS m
ON T BETWEEN ages.age_s AND age_e 
GROUP by ages.age_s +Sep.s+ages.age_e
ORDER BY ages.age_s +Sep.s+ages.age_e asc

Output of the above query

Explanation:

1.  'age_s' and 'age_e' is boundary of age groups like 18-24,25-34
2.  'dob' is the field name where i stored Dob of those who have voted
3.  'VotingInfo' is the table name from where i collect date

 

Data visualized in the application