How to ORDER BY typical software release versions like X.Y.Z?

Question

Given a "SoftwareReleases" table:

| id | version |
|  1 | 0.9     |
|  2 | 1.0     |
|  3 | 0.9.1   |
|  4 | 1.1     |
|  5 | 0.9.9   |
|  6 | 0.9.10  |

How do I produce this output?

| id | version |
|  1 | 0.9     |
|  3 | 0.9.1   |
|  5 | 0.9.9   |
|  6 | 0.9.10  |
|  2 | 1.0     |
|  4 | 1.1     |

Answer 1

To produce your desired output:

SELECT id, version
FROM   versions
ORDER  BY string_to_array(version, '.')::int[];

Cast the whole text array to an integer array (to sort 9 before 10) and ORDER BY that.
This is the same as ordering by each of the elements.
Shorter arrays come before longer ones with an equivalent leading part.

db<>fiddle here
_{Old sqlfiddle}

Answer 2

select id,
       name, 
       v[1] as major_version,
       v[2] as minor_version,
       v[3] as patch_level
from (
   select id, 
          name, 
          string_to_array(version, '.') as v
   from versions
) t
order by v[1]::int desc, v[2]::int desc, v[3]::int desc;

SQLFiddle: http://sqlfiddle.com/#!15/c9acb/1

If you expect more elements in the version string, just use more array indexes. If the index does not exist, the result will be null (e.g. v[10] will return null)

Answer 3

create extension semver;

select id, version from SoftwareReleases order by version::semver;

http://www.pgxn.org/dist/semver/doc/semver.html