Analysis of the return value of the number of rows used by the PHP function mysqli_affected

Analysis of the return value of the number of rows used by the PHP function mysqli_affected_rows

巴扎黑

Release： 2023-03-07 22:04:01

Original

2227 people have browsed it

This article mainly introduces the row number return value of mysqli_affected_rows in PHP. The example analyzes the usage of normal mode and oop mode. It has certain reference value. Friends in need can refer to the example of this article.

Analyzed the row count return value of mysqli_affected_rows in PHP. Share it with everyone for your reference. The specific analysis is as follows:

The number of rows affected by the update operation in mysqli can be returned in two forms:

1. Return the number of matching rows
2. Return the number of affected rows

By default, the value returned by mysqli_affected_rows is the number of affected rows. If we need to return the number of matching rows, we can use the mysqli_real_connect function to initialize the database connection and add:

to the flag parameter of the function.

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

Common format:

The code is as follows:

int mysqli_affected_rows ( mysqli link )

Copy after login

oop format:

The code is as follows:

class mysqli { 
int affected_rows 
}

Copy after login

Look at the example:

Normal mode, The code is as follows:

The code is as follows:

<?php 
$link = mysqli_connect("localhost", "my_user", "my_password", "world"); 
 
if (!$link) { 
printf("Can&#39;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); 
?>

Copy after login

oop mode, the code is as follows:

The code is as follows:

<?php 
$mysqli = new mysqli("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(); 
?>

Copy after login

The above is the detailed content of Analysis of the return value of the number of rows used by the PHP function mysqli_affected_rows. For more information, please follow other related articles on the PHP Chinese website!