SQL & PL/SQL

Hi,

Whenever you have a question, please post a little sample data (CREATE TABLE and INSERT statements, relevant columns only) for all the tables involved, and the exact results you want from that data, so that the people who want to help you can re-create the problem and test their ideas.

Explain, using specific examples, how you get those results from that data.

Always say what version of Oracle you're using (e.g. 11.2.0.2.0).

See the forum FAQ:

Use the analytic ROW_NUMBER function to assign numbers 1, 2, 3, ... to each row, with a separate series for each worker and date.  Each distinct combination of worker and assigned number will result in a row of output.

You will usually get quicker and more accurate answers if you post create table statements and inserts with some sample data, along with an explanation of the specific problem you are facing.

Here is one way to do it:

WITH test_data as
(
SELECT 'Project_A' project,'John' worker,date '2016-05-23' the_date FROM DUAL union all
SELECT 'Project_A','Mary',date '2016-05-23'  FROM DUAL union all
SELECT 'Project_A','Mary',    date '2016-05-24' FROM DUAL union all
SELECT 'Project_A','Steve',date '2016-05-24' FROM DUAL union all
SELECT 'Project_A','Mary',date '2016-05-25' FROM DUAL union all
SELECT 'Project_A','Mary',date '2016-05-26'  FROM DUAL union all
SELECT 'Project_B','John',date '2016-05-23' FROM DUAL union all
SELECT 'Project_B','Steve',date '2016-05-24' FROM DUAL
)
select worker,c23,c24,c25,c26 from
(
  SELECT t.*, dense_rank() over (PARTITION BY worker ORDER BY project) AS rn
  FROM test_data t
)
pivot
(
  MAX(project) FOR the_date in (date '2016-05-23' AS C23,date '2016-05-24' AS C24,date '2016-05-25' AS C25,date '2016-05-26' AS C26)
)
ORDER BY worker;

Results:

You cannot dynamically generate your columns (e.g. generate your column names based on the data) without using special techniques (dynamic SQL), SQL has to have static columns at execution time.

Here's another way to do it.

select worker, d1, d2, d3, d4

from

(

  select project, worker,

         dense_rank() over (order by the_date) as date_rank,

         dense_rank() over (order by project) as project_rank

  from test_data t

)

pivot (

  max(project)

  for date_rank in (1 as D1, 2 as D2, 3 as d3, 4 as d4)

)

order by worker