Random selection problem . . .

[lelyea]

I have a mysql database with a dozen columns, two of which are 'outcome' and 'grade'. I need to write a php script which will query the outcome column for the word "written", count them, and then based on the count UPDATE a fixed percentage of the 'grade' column entries with a numeral 1 randomly. Any advice or examples of how to go about solving this problem would be greatly appreciated.

After reading the 'sticky' note at the head of this forum I feel the need to add that there will never be more than 800 records in this table.

Len

[dagon]

select count(ID) from table where outcome like '%written%'

for the 2nd part i'm not sure what you are asking

[lelyea]

Thanks for the quick reply, dagon. Let me try to explain . . .
I do a:
select count(ID) from table where outcome like '%written%'

on the table and the script returns a count of 200. So, 200 of the 600 rows match. I need to then randomly UPDATE 65% of those rows which matched changing the contents of column 'grade' from the number '0' to the number '1'

[dagon]

you need the rows and a count then a loop to run the update in the selected matches.

[dagon]

actually one update using where id in() would be smarter