Best sollution for date problem.

Question

Hi guys.
I have a table with 100 000 items and it is growing with 50 rows per day. it has a lot of columns and two of them are:
expiration_date date,
status varchar2 (1) ---- A- active and N- Non active.
the expiration_date is a date.
80% of these have status = 'A' and expiration_date in future.
the problem is that I need to create a processes that changes the items status from A to N in exact expiration_date.
exact means: the exact time, or can be 10 minutes or one hour max after that date.
the expiration date can be put manually somewhere in future. when I reach this date, the item need to have the status changed to N.
I was thinking to create a job, that runs each minute. and select all items that are in status A and have expiration_date smaller than sysdate.
my select will be something like.
select * from my_table where expiration_date < sysdate and status = A for update.
for this I will create a composite index on (expiration_date and status).
is there a another solution? can I do something like a 'ticking bomb':) : when expiration_date is updated and set somewhere in future, to set a process that will take care to change the status when that time is reached. doing this I can avoid to scan the index (from the first solution) at every minute.
I use oracle 10G.
Thanks in advance.

Answer 1

alinux wrote:
Hi guys.
I have a table with 100 000 items and it is growing with 50 rows per day. it has a lot of columns and two of them are:
expiration_date date,
status varchar2 (1) ---- A- active and N- Non active.
the expiration_date is a date.
80% of these have status = 'A' and expiration_date in future.
the problem is that I need to create a processes that changes the items status from A to N in exact expiration_date.
exact means: the exact time, or can be 10 minutes or one hour max after that date.
the expiration date can be put manually somewhere in future. when I reach this date, the item need to have the status changed to N.
I was thinking to create a job, that runs each minute. and select all items that are in status A and have expiration_date smaller than sysdate.
my select will be something like.
select * from my_table where expiration_date < sysdate and status = A for update.
for this I will create a composite index on (expiration_date and status).
is there a another solution? can I do something like a 'ticking bomb':) : when expiration_date is updated and set somewhere in future, to set a process that will take care to change the status when that time is reached. doing this I can avoid to scan the index (from the first solution) at every minute.
I use oracle 10G.
Thanks in advance.The BEST solution would be to modify the app so it doesn't rely on a "status" that is derived from a date. Why doesn't the app already know this:
if expiration_date < sysdate
   status is active
else
   status is non active
end ifUse of a data element (in this case STATUS) that can be derived from another data element (in this case EXPIRATION_DATE) is a violation of basic data design 101.