In the MySQL database, you should check the triggers in the database before creating a trigger. This will not only allow developers to have an intuitive grasp of all triggers and functions in the specified database, but also avoid creating new triggers with the same name. or similar functional trigger.
Then we introduced how to create a MySQL trigger in the previous article "MySQL Trigger Creation Trigger" , friends, you can review the knowledge we talked about in the previous article, so today we will mainly introduce to you the view of MySQL triggers!
Technical points:
To view the trigger details in the MySQL database, you can use the following statement:
show triggers
Before using the show triggers statement, you should first specify the database to be viewed~
Implementation process
(1) First create a php file, Create a form form in the php file, enter the database of the trigger you want to view in the input box in the form, and then click the "View" button to display the detailed information of the trigger of the database~
(2) Then we create a connection to the database and select the database to view the triggers!
(3) Finally execute the show triggers statement and use the do{...}while{...} loop to display the detailed information of the found trigger~
Then the above three The specific code of the step is as follows:
<form action="4.php" method="post" name="form1"> 请输入数据库名字: <input type="text" name="username" > <input type="submit" name="Submit" value="查看"> </form> <?php header("Content-Type:text/html; charset=utf-8"); $name = $_POST['username']; $link = mysqli_connect("localhost", "root", "root"); $conn= @mysql_select_db($link,$name); $sql = @mysql_query("show triggers",$link); $info = @mysql_fetch_array($sql); if($info){ echo "该数据库没有设置触发器"; }else{ ?> <table width="600" height="50" border="0" align="center" cellspacing="1" cellpadding="0"> <tr> <td width="156" height="25" bgcolor="#A2D4F4"> <p align='center'>名称</p> </td> <td width="156" height="25" bgcolor="#A2D4F4"> <p align='center'>表名字</p> </td> <td width="156" height="25" bgcolor="#A2D4F4"> <p align='center'>触发事件</p> </td> <td width="156" height="25" bgcolor="#A2D4F4"> <p align='center'>时间</p> </td> <td width="156" height="25" bgcolor="#A2D4F4"> <p align='center'>触发时执行的SQL语句</p> </td> </tr> <?php do{ ?> <tr> <td width="156" height="25" bgcolor="#A2D4F4"> <p align='center'><?php echo $info['Trigger'];?></p> </td> <td width="156" height="25" bgcolor="#A2D4F4"> <p align='center'><?php echo $info['Table'];?></p> </td> <td width="156" height="25" bgcolor="#A2D4F4"> <p align='center'><?php echo $info['Event'];?></p> </td> <td width="156" height="25" bgcolor="#A2D4F4"> <p align='center'><?php echo $info['Timing'];?></p> </td> <td width="156" height="25" bgcolor="#A2D4F4"> <p align='center'><?php echo $info['Statement'];?></p> </td> </tr> <?php }while($info = @mysql_fetch_array($sql)); } ?> </table>
The results obtained by executing the above code example are as follows:
Then we will introduce the content of MySQL triggers here, I believe Friends can easily master the knowledge points we have introduced. We will see you in the next topic~
[Related tutorial recommendations]
1.[MYSQL Online free video tutorial】
2. Recommended related video courses: " Chuanzhi Podcast Liu Daocheng MySql Series Video Tutorial"
The above is the detailed content of MySQL trigger view trigger. For more information, please follow other related articles on the PHP Chinese website!