How to create view on dates for a given month for matrix

Question

hi all
i have the following 2 tables
Task_Master
Task_ID
Task_Name
Task_Details
Task_ID
Task_Date
Task_Count
Both the tables are linked through primary and foreign keys...just want to create a view where i will provide only month and it will return the days like 1-Oct....2-Oct....3-Oct....4-Oct.....5-Oct.... and the Task_Count value under it ..INPUT IS AS FOLLOWS
01/01/2010 How many ATM's issued Today 20
01/02/2010 How many cheque books issued Today 50
01/03/2010 How many cross cheques Today 50
Result required
Task.....................1-Jan..........2-Jan..........3-Jan.........4-Jan........31-Jan
Atms Issued ..........20..............20..............10..............50..............1
Chequebooks.........34..............56................67.............0................67

Answer 1

Hi,
That's called a Pivot , and here's one way to do it:
WITH     start_date     AS
     SELECT     TO_DATE ( '01-Jan-2010'
               , 'DD-Mon-YYYY'
               )     AS start_date
     FROM     dual
SELECT       m.task_name
,       SUM (CASE WHEN TO_CHAR (d.task_date, 'DD') = '01' THEN 1 END)     AS Day_1
,       SUM (CASE WHEN TO_CHAR (d.task_date, 'DD') = '02' THEN 1 END)     AS Day_2
,       SUM (CASE WHEN TO_CHAR (d.task_date, 'DD') = '03' THEN 1 END)     AS Day_3
,       SUM (CASE WHEN TO_CHAR (d.task_date, 'DD') = '31' THEN 1 END)     AS Day_31
FROM       task_master     m
JOIN       task_detail     d     ON     m.task_id     = d.task_id
JOIN       start_date     s     ON     d.task_date     >=            s.start_date
                    AND     d.task_date     < ADD_MONTHS (s.start_date, 1)
GROUP BY  m.task_name
;As posted, this woirks is Oracle 9 (and up).
Starting in Oracle 11, you can also use the SELECT ... PIVOT feature, which is better.