MySQLi
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mysqli->affected_rows

mysqli_affected_rows

(PHP 5)

mysqli->affected_rows -- mysqli_affected_rowsGets the number of affected rows in a previous MySQL operation

说明

Object oriented style (property):

int $affected_rows;

Procedural style:

int mysqli_affected_rows ( mysqli $link )

Returns the number of rows affected by the last INSERT, UPDATE, REPLACE or DELETE query.

For SELECT statements mysqli_affected_rows() works like mysqli_num_rows().

参数

link

Procedural style only: A link identifier returned by mysqli_connect() or mysqli_init()

返回值

An integer greater than zero indicates the number of rows affected or retrieved. Zero indicates that no records where updated for an UPDATE statement, no rows matched the WHERE clause in the query or that no query has yet been executed. -1 indicates that the query returned an error.

Note: If the number of affected rows is greater than maximal int value, the number of affected rows will be returned as a string.

范例

Example #1 Object oriented style

<?php
$mysqli 
= new mysqli("localhost""my_user""my_password""world");

/* check connection */
if (mysqli_connect_errno()) {
    
printf("Connect failed: %s\n"mysqli_connect_error());
    exit();
}

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

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

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

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

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

$result->close();

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

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

Example #2 Procedural style

<?php
$link 
mysqli_connect("localhost""my_user""my_password""world");

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

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

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

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

/* delete rows */
mysqli_query($link"DELETE FROM Language WHERE Percentage < 50");
printf("Affected rows (DELETE): %d\n"mysqli_affected_rows($link));

/* select all rows */
$result mysqli_query($link"SELECT CountryCode FROM Language");
printf("Affected rows (SELECT): %d\n"mysqli_affected_rows($link));

mysqli_free_result($result);

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

/* close connection */
mysqli_close($link);
?>

上例将输出:

Affected rows (INSERT): 984
Affected rows (UPDATE): 168
Affected rows (DELETE): 815
Affected rows (SELECT): 169

参见


MySQLi
PHP 手册