Programming Logic required for pulling the records for past month /week

Question

Hi All
I need help in the SQL programming logic.
Oracle Database Version: 10.2.0.3.0
Requirement
In a data warehouse environment, I need to programme for weekly and monthly automated batch jobs to insert the data from Data_tbl to Reporting_tbl for generating reports. Tables descriptions are given below.
Table1 - Data_tbl (Source table –this table gets updated everyday).
Record_dt     first_name     last_name
Table2 - Reporting_tbl_(Target table)
Cycle_dt     first_name     last_name
1. Monthly Report
In the SQL Query, I have where clause condition—
Where Record_dt >=’01-nov-08’ and record_dt<=’30-nov-08’
Using the above condition in development, I am pulling the data from source table for the past month data. This will be repeated every month and it should be automated.
i.e., if I run this report any time in dec 2008, it should pick records of dates from Nov 01st to Nov 30th 2008. if I run this report any time in Jan 2009, it should pick records of dates from Dec 01st to Dec 31st 2008.
Date Values should be assigned for past month. Value of Cycle_dt in target table should be end date of past month like 30-nov-2008, 31-dec-2008.
2. Weekly Report
In the SQL Query, I have where clause condition—
Where Record_dt >=’01-dec-08’ and record_dt<=’07-dec-08’
Here week start day is Monday and end day is Sunday.
If I run the report between Dec 08th to Dec 14th , it should pull records of dates from Dec 01st to Dec 07th 2008.
On Dec 15th, it should pick from Dec 08th to Dec 14th.
Value of Cycle_dt in target table should be end date of past week like 07-Dec-2008, 14-Dec-2008.
Please help me with the logics for both Monthly and Weekly reports.
Thanks

Answer 1

Hi,
For the monthly report, instead of
Where Record_dt >=’01-nov-08’ and record_dt<=’30-nov-08’say:
Where   Record_dt >= TRUNC (ADD_MONTHS (SYSDATE, -1), 'MM')
and     record_dt <  TRUNC (SYSDATE, 'MM')SYSDATE is the current DATE.
TRUNC (SYSDATE, 'MM') is the beginning of the current month. (Notice the condition above is less than this date, not equal to it.)
ADD_MONTHS (STSDATE, -1) is a date exactly one month ago, therefore it is in the previous month.
For the weekly report, instead of:
Where Record_dt >=’01-dec-08’ and record_dt<=’07-dec-08’say
Where   Record_dt >= TRUNC (SYSDATE - 7, 'IW')
and     record_dt <  TRUNC (SYSDATE, 'IW')TRUNC (dt, 'IW') is the beginning of the ISO week (Monday-Sunday) that contains dt. Again, notice the end condition is strictly less than the beginning of the current week.