Some thoughts...
1. Aren't UUID's "universally unique" by definition? Are you sure you need to do this?
2. Table locking is almost always a bad idea. I had a similar situation to yours in that past, and decided to take the optomistic route, meaning...
- generate the key
- insert the record
- if the insert blows because of a duplicate key, then generate a new key and try again
Since the likelihood of generating a duplicate UUID should be very low, this approcah will work in the vast majority of cases.
Jeff Butler
On 9/15/06, Edwin Lukaweski <[EMAIL PROTECTED]> wrote:
Thanks for the answer.
I am stuck with an existing table definition, in a schema, that I cannot
modify at this point due to being in production.
So, this is the best method I can come up with.
also....now you have tweaked my curiosity. In addition to the advice I
am seeking, it I could alter the table definition to use some form of
auto-increment, how would I retrieve the generated value in iBatis?
So.....I now have two questions.
thanks,
Ediwn
----- Original Message -----
From: "Larry Meadors" < [EMAIL PROTECTED]>
To: <[email protected]>
Sent: Friday, September 15, 2006 10:14 AM
Subject: Re: finding unique keys
> One question: Why not just let the database do it and have it tell you
> the generated key?
>
> Larry
>
>
> On 9/15/06, Edwin Lukaweski <[EMAIL PROTECTED]> wrote:
>>
>>
>> Hi:
>>
>> I have a situation for which I need some advice while using iBatis.
>>
>> What I would like to do is:
>>
>> 1) generate a unique UUID style value in my Java program
>>
>> 2) lock a table, say tabxx
>>
>> 3) SELECT on the table to see if the UUID exists as a key
>>
>> 4) if so, add 1 to the key and go to step 3
>>
>> 5) if the key does NOT exist, insert the record
>>
>> 6) unlock the table
>>
>> Can anyone get me advice as to how to do this with iBatis?
>>
>> Thanks, very musch, in advance
>>
>> Edwin
>>
>
