PHP Common Errors Call fetch_assoc on boolean
Example
If you get an error like this:
Fatal error: Call to a member function fetch_assoc() on boolean in C:\xampp\htdocs\stack\index.php on line 7
Other variations include something along the lines of:
mysql_fetch_assoc() expects parameter 1 to be resource, boolean given...
These errors mean that there is something wrong with either your query (this is a PHP/MySQL error), or your referencing. The above error was produced by the following code:
$mysqli = new mysqli("localhost", "root", "");
$query = "SELCT * FROM db"; // notice the errors here
$result = $mysqli->query($query);
$row = $result->fetch_assoc();
In order to "fix" this error, it is recommended to make mysql throw exceptions instead:
// add this at the start of the script
mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);
This will then throw an exception with this much more helpful message instead:
You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'SELCT * FROM db' at line 1
Another example that would produce a similar error, is where you simply just gave the wrong information to the mysql_fetch_assoc function or similar:
$john = true;
mysqli_fetch_assoc($john, $mysqli); // this makes no sense??
