Update column with random value

问题

I have a table:

ID | VALUE | DATE
1  | 5     | 2012-10-01 
2  | 7     | 2012-10-02
3  | 3     | 2012-10-05
4  | 0     | 2012-05-07 

I want to add on the top of the current value with the VALUE random individually BETWEEN 1 AND 5.

Let say:

ID | VALUE | RANDOM VALUE
1  | 5     | 0
2  | 7     | 2
3  | 3     | 3
4  | 0     | 6 

NEW VALUE

ID | VALUE 
1  | 5     
2  | 9     
3  | 6     
4  | 6      

How do I do this? All I can think of is by doing cursor type of query.

Any help?

回答1:

Try

UPDATE TABLE SET VALUE=VALUE+ROUND(1+RAND()*4);

回答2:

This will update the value by a random value between 1 and 5

UPDATE TABLEA SET VALUE=FLOOR(RAND()*5)+1

来源：https://stackoverflow.com/questions/12972470/update-column-with-random-value