PHP中mysqli_affected_rows作用行数返回值分析

网络编程 2024/11/6 佚名

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本文实例分析了PHP中mysqli_affected_rows作用行数返回值。分享给大家供大家参考。具体分析如下：

mysqli中关于update操作影响的行数可以有两种返回形式:

1. 返回匹配的行数
2. 返回影响的行数

默认情况下mysqli_affected_rows返回的值为影响的行数,如果我们需要返回匹配的行数，可以使用mysqli_real_connect函数进行数据库连接的初始化,并在函数的flag参数位加上:

MYSQLI_CLIENT_FOUND_ROWS return number of matched rows, not the number of affected rows

普通格式:
复制代码代码如下:int mysqli_affected_rows ( mysqli link )

oop格式：
复制代码代码如下:class mysqli {
int affected_rows
}
看下例子：

普通模式,代码如下:
复制代码代码如下:<"localhost", "my_user", "my_password", "world");

if (!$link) {
printf("Can't connect to localhost. Error: %sn", mysqli_connect_error());
exit();
}

/* Insert rows */
mysqli_query($link, "CREATE TABLE Language SELECT * from CountryLanguage");
printf("Affected rows (INSERT): %dn", mysqli_affected_rows($link));

mysqli_query($link, "ALTER TABLE Language ADD Status int default 0″);

/* update rows */
mysqli_query($link, "UPDATE Language SET Status=1 WHERE Percentage > 50″);
printf("Affected rows (UPDATE): %dn", mysqli_affected_rows($link));

/* delete rows */
mysqli_query($link, "DELETE FROM Language WHERE Percentage < 50″);
printf("Affected rows (DELETE): %dn", mysqli_affected_rows($link));

/* select all rows */
$result = mysqli_query($link, "SELECT CountryCode FROM Language");
printf("Affected rows (SELECT): %dn", mysqli_affected_rows($link));

mysqli_free_result($result);

/* Delete table Language */
mysqli_query($link, "DROP TABLE Language");

/* close connection */
mysqli_close($link);
"codetitle">复制代码代码如下:<"localhost", "my_user", "my_password", "world");

/* check connection */
if (mysqli_connect_errno()) {
printf("Connect failed: %sn", mysqli_connect_error());
exit();
}

/* Insert rows */
$mysqli->query("CREATE TABLE Language SELECT * from CountryLanguage");
printf("Affected rows (INSERT): %dn", $mysqli->affected_rows);

$mysqli->query("ALTER TABLE Language ADD Status int default 0″);

/* update rows */
$mysqli->query("UPDATE Language SET Status=1 WHERE Percentage > 50″);
printf("Affected rows (UPDATE): %dn", $mysqli->affected_rows);

/* delete rows */
$mysqli->query("DELETE FROM Language WHERE Percentage < 50″);
printf("Affected rows (DELETE): %dn", $mysqli->affected_rows);

/* select all rows */
$result = $mysqli->query("SELECT CountryCode FROM Language");
printf("Affected rows (SELECT): %dn", $mysqli->affected_rows);

$result->close();

/* Delete table Language */
$mysqli->query("DROP TABLE Language");

/* close connection */
$mysqli->close();
?>