是否可以使用PHP PDO使用第一个表中的列从第二个表中获取数据？

Well, I have a situation that I need to SELECT data from two tables at once. But my main problem is how can I SELECT .. WHERE in my table2 when the value that I needed in WHERE clause is in the return value of SELECT statement in table1.

好吧，我有一种情况需要一次从两个表中选择数据。但我的主要问题是当我在WHERE子句中需要的值在table1中的SELECT语句的返回值时，我如何在table2中SELECT .. WHERE。

test.php

test.php的

<?php 
   include("../../connection.php");
    $data = json_decode(file_get_contents("php://input"));
    $id= $data->id;

    try{
      $db->exec("SET CHARACTER SET utf8");  
      $db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

      $sql = "
        SELECT * FROM tblstudents WHERE studID=':id';
        SELECT * FROM tblparents WHERE studNumber=':studNumber';
      ";

      $statement = $db->prepare($sql);
      $statement->bindValue(":id", $id);
      $statement->bindValue(":studNumber", $studNumber);

      $result = $statement->execute();

      echo json_encode($result);

    }
    catch(PDOException $e) {
      echo $e->getMessage();
    }

?>

The studNumber value is in the tblstudents which will have a return value from SELECT statement.

studNumber值位于tblstudents中，它将具有SELECT语句的返回值。

Is it possible that I can get the studNumber value in the return value of SELECT statement when the SELECT statement of the tblparents is in the same sql query? Or is there another way around?

当tblparents的SELECT语句在同一个sql查询中时，我是否可以在SELECT语句的返回值中获取studNumber值？或者还有另一种方法吗？

Hope I clearly explained my situation.

希望我清楚地解释了我的情况。

1 个解决方案

#1

You need to use JOIN for get data from multiple tables. Try this query:

您需要使用JOIN从多个表中获取数据。试试这个查询：

$sql = "SELECT * FROM tblstudents JOIN tblparents on
 tblstudents.studNumber  = tblparents.studNumber  WHERE tblstudents.studID=:id;"

  $statement = $db->prepare($sql);
  $statement->bindValue(":id", $id);
  $result = $statement->execute();