从不同的数据库表获取搜索结果并显示它们？

Question

I'm trying to create a search function that will retrieve search results for different posters we're creating on our site. If a person is searching for lets say "dog" then it will show the posters which is related to dogs. The site is going to publish different events in the form of posters.

The code looks as following at the moment:

<?php

class Search
{
    public static $con;

    private $search = '';

    function __construct()
    { 
        self::$con = mysqli_connect('localhost', 'guest', 'guestpw', 'db_users');

        $this->search = mysqli_real_escape_string(self::$con, $_POST['search']);
    }

    if(isset($_POST['submit_search']))
    {

    $sql = mysqli_query($con, "SELECT * FROM Event WHERE eventNamn LIKE '%" . $search);

    $sql = mysqli_query($con, "SELECT * FROM Användare WHERE userName LIKE '%" . $search);

    $sql = mysqli_query($con, "SELECT * FROM Poster WHERE Kategori LIKE '%" . $search);

    $sql = mysqli_query($con, "SELECT * FROM EventTyp WHERE EventTyp LIKE '%" . $search);

    $result = mysqli_query($sql);

    }
}

What I want to happen now is to use the search word the user is searching for and then display the events that are associated with that word. All help is much appreciated! Thank you.

Answer 1

The code you're having now is not going to work. You're checking for a $_POST request inside a class? I made some adjustments

<?php

class Search
{
    public static $con;
    private $search = '';

    public function __construct($search)
    { 
        self::$con = mysqli_connect('localhost', 'guest', 'guestpw', 'db_users');

        $this->search = mysqli_real_escape_string(self::$con, $search);
    }

    //Do this for every search

    public function search() {
       $sql = mysqli_query(self::$con, "SELECT [column] FROM Event WHERE eventNamn LIKE '%" .       $search . "'".
"UNION ALL ".
"SELECT [column] FROM Användare WHERE userName LIKE '%" . $search . "'".
"UNION ALL".
"SELECT [column] FROM Poster WHERE Kategori LIKE '%" . $search . "'".
"UNION ALL".
"SELECT [column] FROM EventTyp WHERE EventTyp LIKE'%" . $search . "'");
       return mysqli_query($sql);
    } 
}

if(isset($_POST['search'])) {

  $searchClass = new Search($_POST['search']);
  $result = $searchClass->searchEvent();

}