PHP或MySQL不会更新数据库

Question

Hey guys so I have been trying to figure out why my update function wont update my database.

Here is the function:

public function update() {

    if ( is_null( $this->id ) ) triger_error ("DailyMenuItem::update(): Attempt to update a DailyMenuItem object that does not have its ID property set.", E_USER_ERROR);

    $conn = new PDO ( DB_DSN, DB_USERNAME, DB_PASSWORD );
    $sql = "UPDATE daily_menu SET date=FROM_UNIXTIME(:date), name=:name, description=:description, price=:price WHERE id = :id";
    $st = $conn->prepare ( $sql );
    $st->bindValue( ":name", $this->name, PDO::PARAM_STR );
    $st->bindValue( ":description", $this->description, PDO::PARAM_STR );
    $st->bindValue( ":price", $this->price, PDO::PARAM_INT );
    $st->bindValue( ":date", $this->date, PDO::PARAM_INT);
    $st->execute();
    $conn = null;
}

This object contains this

DailyMenuItem Object ( [id] => 4 [name] => Smoked Chicken Baguette [description] => w/goat cheese [price] => 13 [date] => 1330585200 )

I get no error message. It just does not update anything. Please help :)

Answer 1

You don't seem to be binding id.

Could that be your problem.

Answer 2

In every update and delete query you need an primary key value on which you are performing query. Here in your example you have mentioned ID in the query but there is no bind below so with out the id query will not know which row to be updated.