如何从表中获取唯一的id数组

Question

I have an array of data coming from table. It has number of fields and post_id(int) is one them. I want to get unique value of post_id field of returned array.

$data is returned query

foreach ($data as $key => $get_values) {    
         $post_id = $get_values->post_id;

         $get_query = "select DISTINCT (post_id) from wp_postmeta where post_id = $post_id";

         $get_postId = mysqli_query($get_query);<br>
}  

I want to get DISTINCT (post_id) only.
Any one have solution or any Idea?

Answer 1

Try this

$post_id ="";
foreach ($data as $key => $get_values) {    
$post_id. = $get_values->post_id.",";
}
$post_id =substr($post_id,0,-1);
$get_query = "select DISTINCT (post_id) from wp_postmeta where post_id in ($post_id)";

$get_postId = mysqli_query($get_query);