Php if/else语句中出错

我需要一些帮助使if/else语句在mysql中工作 if语句工作正常，else语句出错。我是布劳尔斯告诉我的

“解析错误：语法错误，在/var/www/domane/public\u html/app/save.php的第48行出现意外的'else'（T_else）”-哪一行是else

它应该获取行的当前值，然后将其添加到新值并更新它

<?php

$dsn = "databasename";
$username="username";
$password="password"; 

try {
  $conn = new PDO($dsn, $username, $password);
  $conn ->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
} catch(PDOException $e) {
  echo "Connection failed: ".$e->getMessage();
}

//------------------------ Does the category already exist in dietTbl? -------------------------
$sql="SELECT COUNT(*) AS subjectcount FROM dietTbl WHERE day=CURDATE()";

try {
                             $st = $conn->prepare($sql);
                             $st->bindValue(":mainsubject",$mainSubject, PDO::PARAM_STR);
                             $st->execute();
                             $row=$st->fetch();
                             $subjectcount=$row["subjectcount"]; // if >0 the yes, the category already exists
} catch (PDOException $e) {
                             echo "Server Error - try again!".$e->getMessage();
};

//------------------------ If it dosn't, insert it into dietTbl -------------------------
if ($subjectcount==0) {

$sql="INSERT INTO dietTbl (day, vegetables, fullgrain, milk, water) values (:day, :vegetables, :fullgrain, :milk, :water)";

try {

  $st = $conn->prepare($sql);
  $st->bindValue(":day",$_POST["day"], PDO::PARAM_STR);
  $st->bindValue(":vegetables",$_POST["vegetables"], PDO::PARAM_STR);
  $st->bindValue(":fullgrain",$_POST["fullgrain"], PDO::PARAM_STR);
  $st->bindValue(":milk",$_POST["milk"], PDO::PARAM_STR);
  $st->bindValue(":water",$_POST["water"], PDO::PARAM_STR);

  $st->execute();
                             } catch (PDOException $e) {
                                                          echo "Server Error - try again!".$e->getMessage();
                             }
};

//------------------------ If it already exists, update dietTbl -------------------------
else {

SELECT SUM(vegetables) AS totalvegetables, SUM(fullgrain) AS totalfullgrain, SUM(milk) AS totalmilk, SUM(water) AS totalwater FROM dietTbl



  $sql="UPDATE INTO dietTbl (vegetables, fullgrain, milk, water) values (:vegetables+totalvegetables, :fullgrain+totalfullgrain, :milk+totalmilk, :water+totalwater)";

try {

  $st = $conn->prepare($sql);
  $st->bindValue(":vegetables",$_POST["vegetables"], PDO::PARAM_STR);
  $st->bindValue(":fullgrain",$_POST["fullgrain"], PDO::PARAM_STR);
  $st->bindValue(":milk",$_POST["milk"], PDO::PARAM_STR);
  $st->bindValue(":water",$_POST["water"], PDO::PARAM_STR);
  $st->execute();
                             } catch (PDOException $e) {
                                                          echo "Server Error - try again!".$e->getMessage();
                             }




};

echo "Information saved";
$conn=null; //Close database connection

?>

---

这部分代码：

};

//------------------------ If it already exists, update dietTbl ----------

else {

删除“；”
删除
之前在线。谢谢。摆脱了那个错误。这是存储现有值的正确方法吗？因为如果似乎不起作用，“选择SUM（蔬菜）作为TotalGreens，SUM（fullgrain）作为totalfullgrain，SUM（milk）作为totalmilk，SUM（water）作为DietBl中的totalwater”在进行第一次修复之前已经在代码中看到太多错误；从第24行，第45行，71@Christoffer如果使用sum，则必须使用group by。使其有效。感谢评论中已经提到的一点