SQL & PL/SQL :: Multiple Record Split On Date Conditions?

Scenario 1 Query should check for priority record(25), if the start_date and end_date of that priority record is the max in that group, records will not have any split.output will be the same.

DC Store St Date End date Priority
955 3 1/1/2010 12/31/9999 25
966 3 4/5/2011 10/10/2011 50
977 3 10/12/2011 12/12/2012 100

output

DC store St Date End date Priority Rank
955 3 1/1/2010 12/31/9999 25 1
966 3 4/5/2011 10/10/2011 50 2
977 3 10/12/2011 12/12/2012 100 3

Scenario 2 If priority record is not covering the max range, then split the records as shown below,

1. during the time period 1/1/2011 & 4/30/2011 there were no other DC for that store so rank would be 1

2. the next range would be 5/1/2011 to 6/29/2011 we have 2 records in service so the record with low priortiy would be ranked 1 and second priority would be ranked 2

3. similarly, for 6/30/2011 to 10/1/2011 we have 3 records in service and it will be ranked accordingly on the priority.

DC Store St Date End date Priority
966 3 6/30/2011 10/1/2011 25
955 3 5/1/2011 11/30/2011 50
977 3 1/1/2011 12/31/2011 100

output

DC store St Date End date Priority Rank
977 3 1/1/2011 4/30/2011 100 1
955 3 5/1/2011 6/29/2011 50 1
977 3 5/1/2011 6/29/2011 100 2

[code]....

Scenario 3 This works similar to scenario 2

DC Store St Date End date Priority
966 3 2/1/2011 12/31/2011 25
955 3 1/1/2011 12/31/2012 50
977 3 5/1/2011 06/31/2011 100

output

DC store St Date End date Priority Rank
955 3 1/1/2011 1/31/2011 50 1
966 3 2/1/2011 12/31/2011 25 1
955 3 2/1/2011 12/31/2011 50 2
977 3 5/1/2011 6/30/2011 100 3
955 3 1/1/2012 12/31/2012 50 1

Note: Number of records in the input can vary and ther can be duplicates in the date interval