(PHP 5)
mysqli_stmt::store_result -- mysqli_stmt_store_result — Transfers a result set from a prepared statement
Object oriented style
Procedural style
You must call mysqli_stmt_store_result() for every query that successfully produces a result set (SELECT, SHOW, DESCRIBE, EXPLAIN), and only if you want to buffer the complete result set by the client, so that the subsequent mysqli_stmt_fetch() call returns buffered data.
Note:
It is unnecessary to call mysqli_stmt_store_result() for other queries, but if you do, it will not harm or cause any notable performance in all cases. You can detect whether the query produced a result set by checking if mysqli_stmt_result_metadata() returns NULL.
Returns TRUE on success or FALSE on failure.
Object oriented style
<?php
/* Open a connection */
$mysqli = new mysqli("localhost", "my_user", "my_password", "world");
/* check connection */
if (mysqli_connect_errno()) {
    printf("Connect failed: %s\n", mysqli_connect_error());
    exit();
}
$query = "SELECT Name, CountryCode FROM City ORDER BY Name LIMIT 20";
if ($stmt = $mysqli->prepare($query)) {
    /* execute query */
    $stmt->execute();
    /* store result */
    $stmt->store_result();
    printf("Number of rows: %d.\n", $stmt->num_rows);
    /* free result */
    $stmt->free_result();
    /* close statement */
    $stmt->close();
}
/* close connection */
$mysqli->close();
?>
Procedural style
<?php
/* Open a connection */
$link = mysqli_connect("localhost", "my_user", "my_password", "world");
/* check connection */
if (mysqli_connect_errno()) {
    printf("Connect failed: %s\n", mysqli_connect_error());
    exit();
}
$query = "SELECT Name, CountryCode FROM City ORDER BY Name LIMIT 20";
if ($stmt = mysqli_prepare($link, $query)) {
    /* execute query */
    mysqli_stmt_execute($stmt);
    /* store result */
    mysqli_stmt_store_result($stmt);
    printf("Number of rows: %d.\n", mysqli_stmt_num_rows($stmt));
    /* free result */
    mysqli_stmt_free_result($stmt);
    /* close statement */
    mysqli_stmt_close($stmt);
}
/* close connection */
mysqli_close($link);
?>
The above examples will output:
Number of rows: 20.