I have a PHP routine that tries to execute two queries, one after the other, and to iterate through the result-set of both.

However, I am finding that, unless I explicitly do a "mysqli_stmt::close()" on the first statement, the second statement(s), although they appear to run, produce no results. (The "affected count," e.g. of a SELECT statement, is zero.)

PHP-7 on the latest Ubuntu.

I'm at a loss to explain this behavior.

$mysqli_stmt->affected_rows returns affected rows with an insert, update or delete query
$mysqli_stmt->num_rows returns rows with a select query but you may need a $mysqli_stmt->store_result() before

(I might have heard something about mysqli being 'less paralelly useable' than mysql. Did your try it with option USE_RESULT or STORE_RESULT?)

Goofy updates: if I close() the first statement-object (my code actually uses a "wrapper" class which encapsulates both a statement and a result handle ...), the next one runs fine.

G-o-o-f-y: If you use different PHP variables each time to store the object (returned by a static "query()" method), it also works. But, if you assign the new object to the same variable ... even though it is obviously a new and different object-instance ... it will not work.

I have an explicit destructor in the object to explicitly close and discard the mysqli objects. I can see that this destructor is running timely. It does not affect anything.

I suspect a flaw either in mysqli or, just as likely, PHP-7 itself.