Any idea how to update table with multiple subjects for one email distribution on % basis in ASP.NET/MySQL.

For example: We have a list of 1000 contacts (email addresses) and want to send email with different subjects on percentage basis.

Email body is same.

User selected # subjects, entered subject names and percentages.

Subject 1 : GPS on sale ------------ (user selected - 30%)
Subject 2: GPS Free------------ (user selected - 50%)
Subject 3: GPS - Upto 70% off------------ (user selected - 20%)

i.e

30% (300) of the emails should go out with Subject 1
50% (500) of the emails should go out with Subject 2
20% (200) of the emails should go out with Subject 3

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Current Scenario:

1. All the above settings are stored in distributionsetup table (emailid, contactlistid, subject1,subject2,subject3, percent1,percent2,percent3,datetobesent etc....)
2. System will insert 1000 rows in distributionqueue table with subject1.
INSERT INTO distributionqueue (subject, fromname, fromemail, tofirstname,tolastname, toemail, company, datetobesent, sentstatus etc...)
SELECT 'GPS on sale' subject, fromname, fromemail, tofirstname,tolastname, toemail, company, '2009-05-20 10:00:00' FROM AddressBook where contactlistid= 1;
3. System will send email to 1000 contacts with the same subject (subject1)
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Requirement :

We need to update distributionqueue table randomly with following criteria.
50% (500) rows should get updated with Subject 2
20% (200) rows should get updated with Subject 3

Hope i explained well, let me know if you have any questions.

Any help highly appreciated.

Thank you

Any idea how to write update command for the above scenario?

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Rams