您需要将结果分配给变量，然后对该变量调用 empty().这只是 empty()函数的一个令人讨厌的限制.参见此问题.

You need to assign the results to a variable, then call empty() on the variable. It's just an annoying limitation of the empty() function. See this question.

$results = $pQuery1->fetch(PDO::FETCH_ASSOC);
if (empty($results)){}