PHP + MYSQL 座位预定系统。计算免费座位

Question

我有一个这样的表:

    $sql = "CREATE TABLE dramaStudio
   (
   rowId varchar(1) not null,
   columnId int not null,
   status int,
   firstName varchar(15) not null,
   lastName varchar(15) not null,
   updatedby varchar(10),
   PRIMARY KEY (rowId, columnId)
   )";

在我网站的主页上，我希望用户能够在不查看座位表的情况下查看是否有空闲座位。几乎只是说“免费座位:”后跟一个数字。我的伪代码逻辑是:

$j=0 
select * from dramaStudio
for every status == 0
    $j+1
echo $j

任何帮助将不胜感激。

Answer 1

假设 status=0 如果有空闲座位:

SELECT COUNT(*) AS freeseats FROM dramaStudio WHERE status=0

完整示例，来自 php 手册:

<?php
  $link = mysqli_connect("localhost", "my_user", "my_password", "world");

  /* check connection */
  if (mysqli_connect_errno()) {
      printf("Connect failed: %s\n", mysqli_connect_error());
      exit();
  }

  $query = "SELECT COUNT(*) AS freeseats FROM dramaStudio WHERE status=0";
  $result = mysqli_query($link, $query);

  /* associative array */
  $row = mysqli_fetch_array($result, MYSQLI_ASSOC);
  echo $row['freeseats']; // this is an integer

  /* free result set */
  mysqli_free_result($result);

  /* close connection */
  mysqli_close($link);
?>