如何在php中显示查询错误[重复]

Question

This question already has an answer here:

• How to get MySQLi error information in different environments? / mysqli_fetch_assoc() expects parameter 1 to be mysqli_result 1 answer

I have a mysqli query that wont execute and I would like to display information about why that's happening. Im just fooling around with this example but I imagine something like this:

$myQuery= $mysqli->query("UPDATE table SET id = 1 WHERE id = 3");
if(!$myQuery) //If query couldnt be executed
{
echo $mysqli->error; //Display information about why wasnt executed (eg. Error: couldnt find table)
}

</div>

Answer 1

try using

// Perform a query, check for error
if (!mysqli_query($con,"UPDATE table SET id = 1 WHERE id = 3"))
{
 echo("Error description: " . mysqli_error($con));
}

mysqli_close($con);