Question

I have a statement like this:

UPDATE `MyTable` 
SET point = point + 1 
WHERE (mySubject = 'MATHEMATICS' AND myGrade = '100') OR 
      (mySubject = 'PHYSICS' AND myGrade = '75') OR 
      (mySubject = 'PHYSICS' AND myGrade = '75')

And I want the table to be updated to:

MATHEMATICS | 100 |  1
PHYSICS     | 75  |  2

instead of

PHYSICS     | 75  | 1

The reason why there is a duplicated ‘PHYSICS’ condition is because I get this information from another function.
And I want to know if I can increment PHYSICS point by two if the other function pass me PHYSICS 2 time.

Is there a way to do this in one connection instead of calling the UPDATE 3 times :

UPDATE `MyTable` SET point = point + 1 WHERE mySubject = 'MATHEMATICS' AND myGrade = '100'
UPDATE `MyTable` SET point = point + 1 WHERE mySubject = 'PHYSICS' AND myGrade = '75'
UPDATE `MyTable` SET point = point + 1 WHERE mySubject = 'PHYSICS' AND myGrade = '75'

Answer 1

When you make UPDATE to table it takes each row ONCE ONLY..
So it wont generate 2 updates for the Physics…

    UPDATE `MyTable` 
SET point = point + 1 
WHERE (mySubject = 'MATHEMATICS' AND myGrade = '100') OR 
      (mySubject = 'PHYSICS' AND myGrade = '75') OR 
      (mySubject = 'PHYSICS' AND myGrade = '75')

This query say’s to the SQL ..
UPDATE for me all rows in MyTable WHERE (case a) or (case b) or (case c)

SQL takes Mathematics and at case a its OK and updated.
Then it takes Physics and at case b they are OK and updated and then sql FINISH because there no more ROWS at table..

You have to make 2 seperated updates to do your job..

UPDATE `MyTable` SET point = point + 1 WHERE mySubject = 'MATHEMATICS';
UPDATE `MyTable` SET point = point + 2 WHERE mySubject = 'PHYSICS';

Or you can use CASE

UPDATE  `MyTable` SET point = 
        CASE
        WHEN mySubject = 'MATHEMATICS' THEN
                (point+1)
        WHEN mySubject = 'PHYSICS' THEN
                (point+2)
        END