Why Does `mysqli_query()` Throw 'expects parameter 1 to be mysqli, null given'?

Understanding "mysqli_query() expects parameter 1 to be mysqli, null given in"

When encountering this error, it indicates a mismatch between the expected data type and the provided value in a MySQLi function. In this specific instance, the query function is not receiving a valid MySQLi object as its first parameter.

In the provided code, you've defined a connection object $con using MySQLi. However, the getPosts() function, where the error occurs, does not have access to this connection object within its scope. Therefore, when attempting to query the database, it passes null instead of the expected mysqli object as the first parameter.

To resolve this issue, you need to make $con accessible within the getPosts() function by passing it as an argument. This allows the function to use the connection object to execute queries properly.

Additionally, it's recommended to catch MySQLi errors and handle them appropriately, such as by halting execution or displaying an error message. This ensures that the application responds to database issues gracefully.

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