Oracle sort values into column - oracle

Question

I have a table like this:
time length name
00:01:00 2 a
00:11:22 2 a
01:01:00 45 a
00:23:00 3 b
and I want to retrieve data from the table in the form:
a b
time length time length
00:01:00 2 00:23:00 3
00:11:22 2
01:01:00 2
so it is a simple task of rearranging data, atm I am doing this in a bash script, but I wonder if there is an easy way to do it in Oracle?

Answer 1

You can use analytical function ROW_NUMBER and full outer join as follows:
WITH CTE1 AS
(SELECT T.*, ROW_NUMBER() OVER (ORDER BY LENGTH, TIME) AS RN FROM YOUR_TABLE T WHERE NAME = 'a'),
CTE2 AS
(SELECT T.*, ROW_NUMBER() OVER (ORDER BY LENGTH, TIME) AS RN FROM YOUR_TABLE T WHERE NAME = 'b')
SELECT A.TIME, A.LENGTH, B.TIME, B.LENGTH
FROM CTE1 A FULL OUTER JOIN CTE2 B
ON A.RN = B.RN
Note: You need to use proper order by to order the records as per your requirement. I have used LENGTH, TIME

Answer 2

You can use a multi-column pivot, by adding an extra column that links the related A and B values; presumably by time order, something like:
select time_col, length_col, name_col,
dense_rank() over (partition by name_col order by time_col) as rnk
from your_table;
TIME_COL LENGTH_COL N RNK
-------- ---------- - ----------
00:01:00 2 a 1
00:11:22 2 a 2
01:01:00 45 a 3
00:23:00 3 b 1
and then pivot based on that:
select *
from (
select time_col, length_col, name_col,
dense_rank() over (partition by name_col order by time_col) as rnk
from your_table
)
pivot (
max(time_col) as time_col, max(length_col) as length_col
for name_col in ('a' as a, 'b' as b)
);
RNK A_TIME_C A_LENGTH_COL B_TIME_C B_LENGTH_COL
---------- -------- ------------ -------- ------------
1 00:01:00 2 00:23:00 3
2 00:11:22 2
3 01:01:00 45
I've left the rnk value in the output; if you don't want that you can list the columns in the select list:
select a_time_col, a_length_col, b_time_col, b_length_col
from ...
Or you could do the same thing with conditional aggregation (which is what pivot uses under the hood anyway):
select
max(case when name_col = 'a' then time_col end) as time_col_a,
max(case when name_col = 'a' then length_col end) as length_col_a,
max(case when name_col = 'b' then time_col end) as time_col_b,
max(case when name_col = 'b' then length_col end) as length_col_b
from (
select time_col, length_col, name_col,
dense_rank() over (partition by name_col order by time_col) as rnk
from your_table
)
group by rnk
order by rnk;
TIME_COL LENGTH_COL_A TIME_COL LENGTH_COL_B
-------- ------------ -------- ------------
00:01:00 2 00:23:00 3
00:11:22 2
01:01:00 45
db<>fiddle