Home Backend Development PHP Tutorial Summary and detailed introduction of php mysqli function (2)

Summary and detailed introduction of php mysqli function (2)

Aug 16, 2019 pm 03:26 PM
mysqli

Foreword: PHP is a programming language that is relatively easy to get started with, and PHP has a lot of built-in functions. Therefore, it is particularly important to understand and master these built-in functions. Next we will analyze some of the built-in functions of PHP.

I will continue to organize it for you in the future.

Recommended php video tutorial: https://www.php.cn/course/list/29/type/2.html

Understanding of phpMysqli functions:

1. What is php mysqli?

php mysqli = php nysqli improved

The mysqli function allows you to access the database server.

Notice! The mysqli extension is available for mysqli version 4.1.13 or newer.

2. How to use mysqli function?

If you want to use the mysqli function, you must add support for the mysqli extension when compiling php.

For more information about installation, please visit: http://www.php.net/manual/en/mysqli.installation.php

For details about running configuration Detailed information address: http://www.php.net/manual/en/mysqli.configuration.php

3. Function introduction:

1, mysqli_query(connection, query, resultmode)Function

resultmode parameter is optional, any one of the following

MYSQLI_STORE_RESULT (Default)

MYSLQLI_USE_RESULT(Available for retrieving large amounts of data)

Description: Execute sql statement

Instance:

<?php
//配置数据库基本信息
$localhost = &#39;localhost&#39;;
$user = &#39;zmz&#39;;
$password = &#39;20040315&#39;;
$dbname = &#39;zmz&#39;;
$port = 3306;

//连接数据库
$conn = mysqli_connect($localhost,$user,$password,$dbname,$port);
//检查连接
if(!$conn) {
die(&#39;连接失败!&#39;.mysqli_connect_error());
}
//连接成功,定义sql语句
$sql = "SELECT * FROM pro1 where 关键
词 like &#39;%么%&#39;";
//执行sql语句
$result = mysqli_query($conn, $sql);
var_dump($result);
mysqli_close($conn);
?>
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2, mysqli_affected_rows()Function

Description: Output the affected rows from different queries Record number of rows:

Instance:

<?php
//配置数据库基本信息
$localhost = &#39;localhost&#39;;
$user = &#39;zmz&#39;;
$password = &#39;20040315&#39;;
$dbname = &#39;zmz&#39;;
$port = 3306;

//连接数据库
$conn = mysqli_connect($localhost,$user,$password,$dbname,$port);
//检查连接
if(!$conn) {
die(&#39;连接失败!&#39;.mysqli_connect_error());
}
//连接成功,定义sql语句
$sql = "SELECT * FROM pro1 where 关键词 like &#39;%么%&#39;";
//执行sql语句
$result = mysqli_query($conn, $sql);
//print_r($result);
//die();
//判断受影响的行数
echo mysqli_affected_rows($conn);
?>
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3mysqli_autocommit()Function

Description: Turn off or enable automatic data submission

Instance:

<?php
//配置数据库信息
$localhost = &#39;localhost&#39;;
$username = &#39;zmz&#39;;
$password = &#39;20040315&#39;;
$dbname = &#39;zmz&#39;;
$port = 3306;

//连接数据库
$conn = mysqli_connect($localhost,$username,$password,$dbname,$port);
//检查连接
if(mysqli_connect_errno($conn)) {
	die(&#39;连接失败!&#39;.mysqli_connect_error());
}
//echo &#39;成功&#39;;
//die();
//连接成功,关闭自动提交
mysqli_autocommit($conn, false);

//执行插入操作
$sql = "INSERT INTO demo (id,name,age)
		VALUES(2,&#39;zmz&#39;,16)";
mysqli_query($conn,$sql);
//手动提交事务
$result = mysqli_commit($conn);
var_dump($result);
//关闭连接
mysqli_close($conn);
?>
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4, mysqli_commit()Function

Description: After turning off automatic submission, manually submit the current transaction transaction of the specified database connection

Instance:

<?php
//配置数据库信息
$localhost = &#39;localhost&#39;;
$username = &#39;zmz&#39;;
$password = &#39;20040315&#39;;
$dbname = &#39;zmz&#39;;
$port = 3306;

//连接数据库
$conn = mysqli_connect($localhost,$username,$password,$dbname,$port);
//检查连接
if(mysqli_connect_errno($conn)) {
die(&#39;连接失败!&#39;.mysqli_connect_error());
}
//echo &#39;成功&#39;;
//die();
//连接成功,关闭自动提交
mysqli_autocommit($conn, false);

//执行插入操作
$sql = "INSERT INTO demo (id,name,age)
VALUES(2,&#39;zmz&#39;,16)";
mysqli_query($conn,$sql);
//手动提交事务
$result = mysqli_commit($conn);
var_dump($result);
//关闭连接
mysqli_close($conn);
?>
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5, mysqli_rollback()Function

Description: Turn off automatic submission, manually commit the transaction, and roll back the current transaction.

Returns true if successful, otherwise returns false.

Example:

<?php
//配置数据库信息
$localhost = &#39;localhost&#39;;
$username = &#39;zmz&#39;;
$password = &#39;20040315&#39;;
$dbname = &#39;zmz&#39;;
$port = 3306;

//连接数据库
$conn = mysqli_connect($localhost,$username,$password,$dbname,$port);
//检查连接
if(mysqli_connect_errno($conn)) {
die(&#39;连接失败!&#39;.mysqli_connect_error());
}
//echo &#39;成功&#39;;
//die();
//连接成功,关闭自动提交
mysqli_autocommit($conn, false);

//执行插入操作
$sql = "INSERT INTO demo (id,name,age)
VALUES(3,&#39;zyl&#39;,22)";
mysqli_query($conn,$sql);
//手动提交事务
$result = mysqli_commit($conn);
mysqli_rollback($conn);
//var_dump($result);
//关闭连接
mysqli_close($conn);
?>
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The above is a supplement to the mysqli function, I hope it will be helpful to everyone. Thanks!

Recommended related articles: https://www.php.cn/php-weizijiaocheng-428624.html

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