douduan3203 2019-03-12 13:38
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为什么这会导致错误的结果呢?

So further to a previous question, I've updated my code to the following

          $stmt = $conn->prepare("SELECT count(id) FROM activities WHERE userId = ? AND status = ? AND DATEDIFF('$date', next_due) >= 1");
          $stmt->bind_param("ss", $userId, $status);
          $stmt->execute();
          $stmt->store_result();
          $numrows = $stmt->num_rows;
          echo $numrows;

It no longer throws an error, but returns $numrows as 1, however I know the number of rows returned should be 2 (I know it should be 2 as I have 2 identical rows in the table for testing purposes). I've tried SELECT count(*), but that also throw a 1 at me.

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  • douhuangjie4503 2019-03-12 14:00
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    COUNT() will always return 1 row. either select the result content or use select id.... and then $stmt->num_rows on the full query

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