


Why Does My PHP Code Show 'Warning: mysqli_select_db() expects exactly 2 parameters, 1 given'?
Missing Parameter in mysqli_select_db(): Warning Demystified
In the realm of PHP programming, it can be frustrating to encounter unexpected errors. One such error that developers may encounter is "Warning: mysqli_select_db() expects exactly 2 parameters, 1 given". Understanding the cause of this error and its solution is crucial for troubleshooting and further development efforts.
What Does the Error Mean?
The error message "Warning: mysqli_select_db() expects exactly 2 parameters, 1 given" indicates that the mysqli_select_db() function is expecting two parameters but only one is being provided. The mysqli_select_db() function is used to select a specific database to work with in the MySQL database management system.
Resolving the Error
To resolve this error, you need to ensure that you are providing both parameters to the mysqli_select_db() function. The first parameter is the connection link, which is a variable that represents an active connection to the MySQL database. The second parameter is the name of the database that you want to select.
Example
In your example code, the mysqli_select_db() function is missing the second parameter, the database name. To fix this, you should add the database name to the function call, like so:
mysqli_select_db($con, 'phpcadet');
Where:
- $con is the connection link variable
- phpcadet is the name of the database you want to select
By providing both parameters, you should be able to successfully select the database and proceed with your development tasks without encountering the "Warning: mysqli_select_db() expects exactly 2 parameters, 1 given" error.
The above is the detailed content of Why Does My PHP Code Show 'Warning: mysqli_select_db() expects exactly 2 parameters, 1 given'?. For more information, please follow other related articles on the PHP Chinese website!

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