What is causing PDO error Cannot execute queries while other unbuffered queries are active?

Question

I have the following code:

$dbh = new PDO(\"mysql:host=$host;dbname=$dbname\", $user, $pass);
$dbh->setAttribute(PDO::ATTR_EMULATE_PREPARES, false);
$dbh->         


        

Answer 1

This is not necessarily the answer to this question, but this may help somebody in the future.

I came across exactly the same error and it took hours to discover what was wrong. It turned out it was just a extremely minor syntax issue all along. If you're not actually using any buffering, but still have this error, like I did, this could be your issue - so check your code.

I was doing my normal database queries when I came across this error -- not purposely using any buffering techniques -- so I highly doubted it had anything to do with buffering. I read every SO question about it and looked deeper in to it.

This was my STUPID syntax issue:

$SQL = "UPDATE articles SET
            topicID = :topic;    <-------- semicolon - woops!
            heading = :heading,
            subheading = :subheading,
            keywords = :keywords,
            rawContent = :rawContent,
            content = :content,
            ...
            ...

This resulted in me getting this buffering error. I fixed the code and it went away. What was most annoying, was the fact the PDO error was pointing at another query, the next query, but that query was in a function elsewhere in the code, and that through me well off course for a while!