How to handle database connection errors in PHP
Jun 05, 2024 pm 02:16 PM
To handle database connection errors in PHP, you can use the following steps: Use mysqli_connect_errno() to get the error code. Use mysqli_connect_error() to get the error message. By capturing and logging these error messages, database connection issues can be easily identified and resolved, ensuring the smooth running of your application.
How to Handle Database Connection Errors in PHP
Database connection issues are a common problem that developers often encounter. In PHP, these errors can be handled efficiently by using the mysqli_connect_errno() and mysqli_connect_error() functions in the mysqli extension.
Method:
-
Use
mysqli_connect_errno()Get the error code:$errno = mysqli_connect_errno();
errnoThe variable will contain a numeric error code indicating the specific error that occurred. Use
mysqli_connect_error()to get the error message:$errmsg = mysqli_connect_error();
errmsgThe variable will contain the error Message text, providing more information about the error.
Practical case:
Consider the following code, which attempts to connect to the database:
<?php
$mysqli = new mysqli("localhost", "my_user", "my_password", "my_db");
if ($mysqli->connect_errno) {
echo "連接失?。?" . $mysqli->connect_errno . ") " . $mysqli->connect_error;
} else {
echo "連接成功！";
}
?>If the database connection fails, the Output the error code and error message as follows:
連接失?。?2002) No connection could be made because the target machine actively refused it.
By capturing and recording these error messages, developers can easily identify and resolve database connection issues to ensure the smooth operation of the application.
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