How to add new column to MYSQL table?

Question

I am trying to add a new column to my MYSQL table using PHP. I am unsure how to alter my table so that the new column is created. In my assessment table I have:

Answer 1

• You can add a new column at the end of your table

  ALTER TABLE assessment ADD q6 VARCHAR( 255 )

• Add column to the begining of table

  ALTER TABLE assessment ADD q6 VARCHAR( 255 ) FIRST

• Add column next to a specified column

  ALTER TABLE assessment ADD q6 VARCHAR( 255 ) after q5

and more options here

Answer 2

You should look into normalizing your database to avoid creating columns at runtime.

Make 3 tables:

1. assessment
2. question
3. assessment_question (columns assessmentId, questionId)

Put questions and assessments in their respective tables and link them together through assessment_question using foreign keys.

Answer 3

for WORDPRESS:

global $wpdb;


$your_table  = $wpdb->prefix. 'My_Table_Name';
$your_column =                'My_Column_Name'; 

if (!in_array($your_column, $wpdb->get_col( "DESC " . $your_table, 0 ) )){  $result= $wpdb->query(
    "ALTER     TABLE $your_table     ADD $your_column     VARCHAR(100)     CHARACTER SET utf8     NOT NULL     "  //you can add positioning phraze: "AFTER My_another_column"
);}

Answer 4

Based on your comment it looks like your'e only adding the new column if: mysql_query("SELECT * FROM assessment"); returns false. That's probably not what you wanted. Try removing the '!' on front of $sql in the first 'if' statement. So your code will look like:

$sql=mysql_query("SELECT * FROM assessment");
if ($sql) {
 mysql_query("ALTER TABLE assessment ADD q6 INT(1) NOT NULL AFTER q5");
 echo 'Q6 created'; 
}else...

Answer 5

your table:

q1 | q2 | q3 | q4 | q5

you can also do

ALTER TABLE yourtable ADD q6 VARCHAR( 255 ) after q5

Answer 6

ALTER TABLE `stor` ADD `buy_price` INT(20) NOT NULL ;