mysqli_query() Expects Parameter 1 to be mysqli, Resource Given

When attempting to execute a MySQL query using the mysqli_query() function, the "Warning: mysqli_query() expects parameter 1 to be mysqli, resource given" error can occur. This error indicates a mismatch between the type of the first parameter and the expected resource type.

Root Cause:

The root cause of this error is typically related to mixing the mysqli and mysql extensions within your code. These two extensions are not interchangeable and cannot be used together.

Solution:

To resolve this issue, ensure that you are using the same extension throughout your code. If you are using the mysqli extension, all database-related functions must use the mysqli prefix, such as mysqli_connect(), mysqli_select_db(), and mysqli_query().

In the example provided, the code contains mixings of mysql and mysqli functions. To fix it, replace the following lines:

$myConnection= mysql_connect("$db_host","$db_username","$db_pass") or die ("could not connect to mysql");
mysql_select_db("mrmagicadam") or die ("no database");

with:

$myConnection= mysqli_connect("$db_host","$db_username","$db_pass") or die ("could not connect to mysql");
mysqli_select_db($myConnection, "mrmagicadam") or die ("no database");

By making this change, you are ensuring that all database-related functions are using the correct extension, which will eliminate the error and allow the MySQL query to execute successfully.