PHP中mysqli_affected_rows作用行数返回值分析

  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:
<?php

  $link = mysqli_connect("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);

  ?>

  oop模式,代码如下:

  

复制代码 代码如下:
<?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();

  ?>

  希望本文所述对大家的php程序设计有所帮助。