SQL选择数组中的所有内容

Question

我的作业有一个问题，例如有一个类别数组$ cat = array（'1'，'4'，'5'，'7'）;现在我需要从基于类别的数据库中选择产品

SELECT * FROM products WHERE catid='1' 
SELECT * FROM products WHERE catid='4' 
SELECT * FROM products WHERE catid='5' 
SELECT * FROM products WHERE catid='7' 

是否有可能在单个查询中执行此操作？因为四个查询的最终结果将被结合。

Answer 1

SELECT * FROM products WHERE catid IN ('1', '2', '3', '4') 

Answer 2

$SQL_Part="(" 
$i=0; 
while ($i<length($cat)-1) 
{ 
    $SQL_Part+=$cat[i]+","; 
} 
$SQL_Part=$SQL_Part+$cat[$i+1]+")" 

$SQL="SELECT * FROM products WHERE catid IN "+$SQL_Part; 

它更通用的，将适合任何阵！

Answer 3

// array of $ids that you need to select 
$ids = array('1', '2', '3', '4', '5', '6', '7', '8'); 

// create sql part for IN condition by imploding comma after each id 
$in = '(' . implode(',', $ids) .')'; 

// create sql 
$SQL = 'SELECT * FROM products WHERE catid IN ' . $in; 

// see what you get 
var_dump($sql);