SQL query between strings representing version numbers - sql

Question

I have a SQL query that goes like this:
select v FROM v.rsversion between 'minVer' and 'maxVer';
Where the version is expressed as a string of format x.y.z
This will return fine all existing versions between 0.2.0 and 0.2.9
but will return nothing if the range is 0.2.0 and 0.2.10
Is there a way to make this work?

Answer 1

With Postgres you could do this by splitting up the version into three numbers and then compare those numbers. For other DBMS you would need to find a different way of splitting a string like 0.2.1 into three numbers.
with rsversion (v) as (
values
-- only here for sample data
('0.2.0'), ('0.2.1'), ('0.2.2'), ('0.2.10'), ('0.2.12'),
('0.3.0'), ('0.3.1'), ('0.3.2'), ('0.3.4')
), numeric_version (v, major, minor, patch) as (
select v,
split_part(v,'.', 1)::int,
split_part(v,'.', 2)::int, ,
split_part(v,'.', 3)::int
from rsversion
)
select v
FROM numeric_version
where (major,minor,patch) between (0,2,1) and (0,2,11)
The above prints:
v
------
0.2.1
0.2.2
0.2.10
SQLFiddle example: http://sqlfiddle.com/#!15/403d2/2

Answer 2

The reason this is not working as designed is because 0.2.0 and 0.2.x are not literal numbers, so if you are trying to do a string comparison it's looking at each incremented character and comparing them.
So 0.2.0, 0.2.1, 0.2.10, 0.2.2, 0.2.3, etc is how it's arranging the strings.
You may be able to make this work by adding a leading 0 to the third part of the string 0.2.00, 0.2.01, 0.2.02, etc if that is possible to do for your purposes.

Answer 3

Does this work? I'm assuming your version will always be in a similar format and that your minVer and maxVer are stored as text.
WITH
DATA AS
(
SELECT whatever other data you require,
SUBSTRING(v.rsversion FROM '^[0-9]+.[0-9]+'), '.', '')::decimal as version_part_one,
SUBSTRING(v.rsversion FROM '[0-9]+$')::decimal as version_part_two
FROM v
)
SELECT d.whatever other data you require
FROM data d
WHERE d.version_part_one >= SUBSTRING(minVer FROM '^[0-9]+.[0-9]+')::decimal
AND
d.version_part_two >= SUBSTRING(minVer FROM '.[0-9]+$')::decimal
AND
d.version_part_one <= SUBSTRING(minVer FROM '^[0-9]+.[0-9]+')::decimal
AND
d.version_part_two <= SUBSTRING(maxVer FROM '.[0-9]+$')::decimal
You can change the name of the CTE if you're feeling more creative...