mysqli :: $ affected_rows和mysqli_stmt :: $ affected_rows之间有什么区别？

Question

Obviously, mysqli_stmt::$affected_rows is not available unless prepared statements are being used. But when prepared statements are being used, what's the difference between mysqli::$affected_rows and mysqli_stmt::$affected_rows?

I have the same question in regards to mysqli::$insert_id vs mysqli_stmt::$insert_id.

I'm trying to decide if I should be using one in favour of the other.

I've read the PHP manual entries for these properties. I've done some testing (PHP 5.3.17) using a single execute and using multiple executes. I don't see a difference.

So I am wondering if maybe there is some difference under certain circumstances (or certain versions). If they are exactly the same, why have both?

Answer 1

mysqli_stmt::$affected_rows:

Returns the total number of rows changed, deleted, or inserted by the last executed statement

mysqli::$affected_rows:

Gets the number of affected rows in a previous MySQL operation

So, if the mysqli_stmt object was the last executed statement, both queries should give the same result.