在每个函数中打开和关闭mysql的不良做法

Question

Example:

class SimpleClass{
  public function foo() {
    mysql_open();
    //do mysql query here
    mysql_close();
  }

  public function boo() {
    mysql_open();
    //do mysql query here
    mysql_close();
  }
}

Or is it better to have one mysql_open in the beginning of the class and one in the end?

Thanks.

EDIT: I use mysqli, this is just an example. Should I open and close in each page file instead? Like in index.php, cataegory.php should have one open and close each.

Answer 1

Yes, It is bad practice. Here are reasons:

• cost of making connectio is high
• cannot use transaction during many function is called
• every instance has it's own connection. It's too bad
• and so on

Use PDO, or make singleton db class youself.