How to fetch data based on dates ?

Question

How do i write the query for the below statements ?
1) net_bank_cr from rm_memorandum for the previous year end 31st March
2) net_bank_cr from rm_memorandum for the as on date
3) net_bank_cr from rm_memorandum as one year prior to current reporting date
The table structure of rm_memorandum is as given below:
create table RM_MEMO
AS_ON_DT DATE,
PAID_CAPITAL NUMBER(20,2),
TOTAL_OBE NUMBER(20,2),
CR_EQI_OBE NUMBER(20,2),
NET_BANK_CR NUMBER(20,2),
ADJ_NET_BANK_CR NUMBER(20,2),
DEP_CURREMT_CRR NUMBER(20,2),
LIAB_OTH_CRR NUMBER(20,2),
TOTAL_CRR NUMBER(20,2)
)

Answer 1

The following result includes all rows for the previous financial year relative to the current date.
SQL> with t as
  2  (
  3    select to_date('31/12/2010', 'dd/mm/yyyy') As_On_Dt, 205 Net_bank_CR from dual union all
  4    select to_date('15/03/2011', 'dd/mm/yyyy'), 205  from dual union all
  5    select to_date('15/03/2011', 'dd/mm/yyyy'), 666  from dual union all
  6    select to_date('31/03/2011', 'dd/mm/yyyy'), 9856 from dual union all
  7    select to_date('31/03/2011', 'dd/mm/yyyy'), 521  from dual union all
  8    select to_date('05/04/2011', 'dd/mm/yyyy'), 20   from dual union all
  9    select to_date('07/05/2011', 'dd/mm/yyyy'), 965  from dual
10  )
11  --
12  select *
13  from t
14  where  t.As_On_Dt between (case
15                              when ( sysdate >  add_months(trunc(t.As_On_Dt, 'YYYY'), 3) - 1 ) then
16                                add_months(trunc(add_months(sysdate, -12), 'YYYY'), 3) - 1
17                              when ( sysdate <= add_months(trunc(t.As_On_Dt, 'YYYY'), 3) - 1 ) then
18                                add_months(trunc(add_months(sysdate, -24), 'YYYY'), 3) - 1
19                            end) + 1 -- plus 1 to ensure it is the 1st Apr
20                     and
21                            case
22                             when ( sysdate >  add_months(trunc(t.As_On_Dt, 'YYYY'), 3) - 1 ) then
23                               add_months(trunc(sysdate, 'YYYY'), 3) - 1
24                             when ( sysdate <= add_months(trunc(t.As_On_Dt, 'YYYY'), 3) - 1 ) then
25                               add_months(trunc(add_months(sysdate, -12), 'YYYY'), 3) - 1
26                            end
27  /
AS_ON_DT  NET_BANK_CR
31-DEC-10         205
15-MAR-11         205
15-MAR-11         666
31-MAR-11        9856
31-MAR-11         521Edited by: bluefrog on Sep 7, 2011 1:35 PM Ensure it is the 1st of Apr as the first date, hence add 1