Question

我在php中有一个for循环，但不能正常工作。在for循环中，我有一个“ if”和一个“ else”，但是循环在第一个“ else”中停止迭代，应该继续。这是代码：

//counting the rows in database and the rows I want to insert

$total = count($rowToInsert); //for example 10 values
$totalDB = count($rowDB); // for example 5 values

// the for loop starts

for ($i=0; $i < $total; $i++){ //it should iterate until 10 values

  if(isset($rowDB[$i])){ //change the first 5 values

   $update = "UPDATE table SET name = '$name[$i]' WHERE ID = $rowToInsert[$i]";
   $result = mysqli_query($con, $update);

  } else { //it should iterate from sixth until tenth value

   $insert = "INSERT INTO table (name) VALUES ('$name[$i]')";
   $result = mysqli_query($con, $insert);

  // here is the next code

  $newTable = 'table'.$rowToInsert[$i];

  $newDB = "CREATE DATABASE $newTable CHARACTER SET utf8 COLLATE utf8_general_ci";
  $resultDB = mysqli_query($con, $newDB);

  // select the DB

  mysqli_select_db($con, $newTable) or die ("not found");

  } //end of else

} //end of for

问题是，如果数据库包含5行，而我想插入10行，则代码将使用新值更新前5行，然后跳转到“ else”并开始在第六个值，它起作用，但下一个值不起作用。

知道我在做什么错吗？谢谢！

赫克托

Answer 1

好，我发现了问题。在else循环中，当迭代尝试选择数据库时，由于某种原因，它使用了上一次迭代的名称，因此找不到数据库。解决方案（也许不是那么干净）是在每次迭代中连接并关闭数据库连接。代码如下：

//counting the rows in database and the rows I want to insert

$total = count($rowToInsert); //for example 10 values
$totalDB = count($rowDB); // for example 5 values

// the for loop starts

for ($i=0; $i < $total; $i++){ //it should iterate until 10 values

  if(isset($rowDB[$i])){ //change the first 5 values

   $update = "UPDATE table SET name = '$name[$i]' WHERE ID = $rowToInsert[$i]";
   $result = mysqli_query($con, $update);

  } else { //it should iterate from sixth until tenth value

   // reconnect to db

   $con = mysqli_connect($host, $user, $pass) or die ("unable to connect");
   $db = "database";

   $insert = "INSERT INTO table (name) VALUES ('$name[$i]')";
   $result = mysqli_query($con, $insert);

  // here is the next code

  $newTable = 'table'.$rowToInsert[$i];

  $newDB = "CREATE DATABASE $newTable CHARACTER SET utf8 COLLATE utf8_general_ci";
  $resultDB = mysqli_query($con, $newDB);

  // select the DB

  mysqli_select_db($con, $newTable) or die ("not found");

  //close the connection to db;

  $con->close();

  } //end of else

} //end of for

感谢大家启发答案！

赫克托

循环使用php在mysql数据库中插入行

1 个答案: