Database design question - Using Field definition table

Hi,
We have a table similar to the following schema.
Product table
product_id int,
product_name varchar(50),
product_desc varchar(100),
product_price money,
product_sub_category_id int
We also have tables for product category and sub category. We would
like to save audit trail information whenever a new product is added,
changed name, description or price, and moved to another sub category
or category. We need to save modified user, modification datetime and
some other audit info as well. It seems there are two options available
saving this data i.e. either using a large table that has all audit
columns or using field definition table. The field definition table has
a field id and audit field column and the audit table will have
product_id, modified field id, new value, old value, modified user and
modification date.
My question is which design is efficient? It seems the first is pretty
straight forward and easy to implement, but stores redundant
information and grows quickly. The second solution seems to reduce
redundancy, but end up saving multiple rows if there are multiple
updates at one time. Also, we need to make join to the same table when
we write complex queries.
Any comments or suggestions would be appreciated.
Thanks,It sounds like you already understand the tradeoffs pretty well, at
least between the alternatives given.
Not knowing the details of your operation makes it hard to give
meaningful advice. Just looking at the given information, I have to
suspect that the most common change would be to product_price. It
also makes me wonder if the price does not belong in a price table
instead, with effective dates and who-changed-it-when information. In
that configuration the price table itself becomes its own audit table.
If changes to the rest of the columns are infrequent enough then that
would allow the simple approach of duplicating the entire row for the
other columns. When space permits I much prefer the simple approach,
as it makes using the audit data so much simpler.
Roy Harvey
Beacon Falls, CT
On 5 Jul 2006 16:12:54 -0700, sreedhardasi@.gmail.com wrote:

>Hi,
>We have a table similar to the following schema.
>Product table
> product_id int,
> product_name varchar(50),
> product_desc varchar(100),
> product_price money,
> product_sub_category_id int
>We also have tables for product category and sub category. We would
>like to save audit trail information whenever a new product is added,
>changed name, description or price, and moved to another sub category
>or category. We need to save modified user, modification datetime and
>some other audit info as well. It seems there are two options available
>saving this data i.e. either using a large table that has all audit
>columns or using field definition table. The field definition table has
>a field id and audit field column and the audit table will have
>product_id, modified field id, new value, old value, modified user and
>modification date.
>My question is which design is efficient? It seems the first is pretty
>straight forward and easy to implement, but stores redundant
>information and grows quickly. The second solution seems to reduce
>redundancy, but end up saving multiple rows if there are multiple
>updates at one time. Also, we need to make join to the same table when
>we write complex queries.
>Any comments or suggestions would be appreciated.
>Thanks,|||Hi
I agree with Roy , you will be benefit from having price's table . Much
easier to audit instead of having triggers or something else to track the
info
<sreedhardasi@.gmail.com> wrote in message
news:1152141174.756626.230500@.v61g2000cwv.googlegroups.com...
> Hi,
> We have a table similar to the following schema.
> Product table
> product_id int,
> product_name varchar(50),
> product_desc varchar(100),
> product_price money,
> product_sub_category_id int
> We also have tables for product category and sub category. We would
> like to save audit trail information whenever a new product is added,
> changed name, description or price, and moved to another sub category
> or category. We need to save modified user, modification datetime and
> some other audit info as well. It seems there are two options available
> saving this data i.e. either using a large table that has all audit
> columns or using field definition table. The field definition table has
> a field id and audit field column and the audit table will have
> product_id, modified field id, new value, old value, modified user and
> modification date.
> My question is which design is efficient? It seems the first is pretty
> straight forward and easy to implement, but stores redundant
> information and grows quickly. The second solution seems to reduce
> redundancy, but end up saving multiple rows if there are multiple
> updates at one time. Also, we need to make join to the same table when
> we write complex queries.
> Any comments or suggestions would be appreciated.
> Thanks,
>|||Thanks a lot for your suggestions. I think it is a good idea to have a
price table.
Uri Dimant wrote:[vbcol=seagreen]
> Hi
> I agree with Roy , you will be benefit from having price's table . Much
> easier to audit instead of having triggers or something else to track the
> info
>
> <sreedhardasi@.gmail.com> wrote in message
> news:1152141174.756626.230500@.v61g2000cwv.googlegroups.com...|||Thanks a lot for your suggestions. I think it is a good idea to have a
price table.
Uri Dimant wrote:[vbcol=seagreen]
> Hi
> I agree with Roy , you will be benefit from having price's table . Much
> easier to audit instead of having triggers or something else to track the
> info
>
> <sreedhardasi@.gmail.com> wrote in message
> news:1152141174.756626.230500@.v61g2000cwv.googlegroups.com...