通过乘法和四舍五入更新列值

i want to multiply my db column( ".$subject_column."_theory) value with 10/7( my subject total is 70, and i want to convert it to 100 for finding the grade.) also after multiplication the result must be rounded off

    $update_subject_statement4 = "UPDATE ".$track_table_name."

    SET `".$subject_column."` =IF(`".$subject_column."_theory`='ab',0,`".$subject_column."_theory`) WHERE
                                     evaluation_division="."'$eval_div' AND evaluation_config_id = ".$config_id." AND stream_index = ".$stream_index;   
                                    $additional_sum_update_query = $this->db->query($update_subject_statement4);

$update_subject_statement4 = "UPDATE ".$track_table_name."

SET `".$subject_column."` = ROUND(IF(`".$subject_column."_theory`='ab',0,`".$subject_column."_theory`) * 7 / 10) 
WHERE
evaluation_division="."'$eval_div' 
AND evaluation_config_id = ".$config_id." 
AND stream_index = ".$stream_index;   

$additional_sum_update_query = $this->db->query($update_subject_statement4);

1st: we multiplied your value with 7/10

IF(".$subject_column."_theory='ab',0,".$subject_column."_theory) * 7 / 10

2nd: we rounded it

ROUND( IF(".$subject_column."_theory='ab',0,".$subject_column."_theory) * 7 / 10 )