检查表的字段是否设置了NOT NULL属性

Question

I want to check whether a field in a table has been defined with NOT NULL.

So Lets say I have the following code to create an sql query:

$sql = "CREATE TABLE `testdb`.`test` (`a` INT NULL, `b` INT NOT NULL DEFAULT \'2\');";

Now I want to write some code in php that can query the table as to whether or not field b is defined as NOT NULL or not. I suppose the more general question here is how to query a table for the properties of its fields.

Answer 1

Here you go:

$table = 'my_table';
$result = mysql_query('DESCRIBE `' . $table . '`');

while($item = mysql_fetch_assoc()){
    print_r($item); // this will output the properties of the table
}

In $item you'll now have a property called Null which is either NO or YES.