Creating buckets to categorize the values using MySQL - mysql

Question

Hi I am trying to create a buckets for a very large number of rows. I have a maximum value of 9759721 and a minimum value of 1006909. I would like to show the results as following:
distance
bucket
range
1006909
0
1000000 - 1009999
1013525
1
1010000 - 1019999
1021948
2
1020000 - 1029999
The table might not be so clear but in general, I would like to break down them by a change of 10000. Creating a new bucket once every 10000 starting from 1000000.
I tried the following code but it doesn't show the correct output.
select distance,floor(distance/10000) as _floor from data;
I got something like:
distance
bucket
1006909
100
1013525
101
1021948
102
1035472
103
1042069
104
9759721
975
This seems to be correct but I need the bucket to start from 0 and then change based on 10000. And then have a range column as well. The minimum value that I have for distance is 1006909 and so the data doesn't start with 0 but is it possible to still have a bucket column starting from 0 [i.e assigned to minimum distance].

Answer 1

SELECT
d.distance,
DENSE_RANK() OVER (ORDER BY d._floor) - 1 AS bucket,
d._floor * 10000 AS bucket_lower_limit,
d._floor * 10000 + 10000 AS bucket_upper_limit
FROM
(
SELECT
distance,
FLOOR(distance / 10000) AS _floor
FROM
data
)
AS d
NOTE: the will give buckets numbered from 0 upwards, but will also remove all gaps (such that you sample data will have bucket 5 for the last row, not bucket 975)
Alternatively, if you need to preserve the gaps...
SELECT
d.distance,
d._floor - MIN(d._floor) OVER () AS bucket,
d._floor * 10000 AS bucket_lower_limit,
d._floor * 10000 + 10000 AS bucket_upper_limit
FROM
(
SELECT
distance,
FLOOR(distance / 10000) AS _floor
FROM
data
)
AS d

Answer 2

Just calculate 1006909 div 10000 * 10000 = 1000000 and subtract it from distance. That'll make the buckets start from 0:
SELECT distance
, (distance - a) div 10000 AS bucket
, distance div 10000 * 10000 AS range_from
, distance div 10000 * 10000 + (10000 - 1) AS range_to
FROM t
CROSS JOIN (
SELECT MIN(distance) div 10000 * 10000 AS a
FROM t
) AS x
SQL Fiddle