MySQL WHERE something = $ something和$ something =默認情況下的每個值

Question

我正在嘗試爲我的網上商店做一個過濾器。 我有以下查詢

$column = mysqli_query($link, "SELECT brand FROM shields WHERE 
brand=".$brand." ORDER BY id DESC LIMIT ".$offset. "," . $itemsPerPage); 

我想$brand等於1，2和3默認顯示在我的店裏每一個項目，當我過濾那就改變$brand到1，2或3與此代碼

$brand = filter_input(INPUT_GET, 'brand', FILTER_VALIDATE_INT); 

Answer 1

你可以這樣：

if(isset($_POST["brand"])){ 
    $brand = $_POST["brand"]; // filter_input(INPUT_GET, 'brand', FILTER_VALIDATE_INT); 
    $filterByBrand = "and brand =".$brand; 
} 
else{ 
    $brand = "1,2,3"; 
    $filterByBrand = "and brand in(".$brand.")"; 
} 


$column = mysqli_query($link, "SELECT brand FROM shields WHERE 1=1 
".$filterByBrand." ORDER BY id DESC LIMIT ".$offset. "," . $itemsPerPage);