Php/docs/mysqli.affected-rows
mysqli::$affected_rows
mysqli_affected_rows
(PHP 5, PHP 7)
mysqli::$affected_rows -- mysqli_affected_rows — Gets the number of affected rows in a previous MySQL operation
说明
面向对象风格
int $mysqli->affected_rows;
过程化风格
mysqli_affected_rows
( mysqli $link
) : int
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().
返回值
An integer greater than zero indicates the number of rows affected or
retrieved.
Zero indicates that no records were 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 the maximum integer value(
PHP_INT_MAX), the number of affected rows will be returned as a string.
范例
Example #1 $mysqli->affected_rows example
面向对象风格
<?php$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();?>
过程化风格
<?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);?>
以上例程会输出：
Affected rows (INSERT): 984 Affected rows (UPDATE): 168 Affected rows (DELETE): 815 Affected rows (SELECT): 169
