如何使用PHP和Codeigniter处理foreach中的mysql中的SELECT（MAX（））

Question

I'm using SELECT(MAX()) inside a foreach loop and this is my code:

foreach($_POST['image_Basename'] as $key=>$image_Basename){


    $image_Title = $this->input->post('image_Title');

    $image_Category_Id = $this->input->post('image_Category_Id');


    $this->db->query("INSERT INTO mg_gallery (image_Group_Id, image_title, image_Basename, image_Category_Id)
                      SELECT 1 + coalesce((SELECT max(image_Group_Id) FROM mg_gallery), 0), '$image_Title', '$image_Basename', '$image_Category_Id'
    ");
}

The problem is that for each image_Basename, query produces a new number.

For example, if I got 3 image_Basenames, it will insert 1, 2 and 3 for those three image_Basenames. But I want it to insert the same number to all of image_Basenames.

For example, if the max number in the image_Group_Id is 1, then add number 2 for each image_Basename. How can I do that?! I've put

SELECT 1 + coalesce((SELECT max(image_Group_Id) FROM mg_gallery

outside of the foreach loop, but it didn't work!!!

The answer is added below by myself

Answer 1

IT WORKS:

Specially thanks to Niloy Saha, finally, I got the answer, and this is the code I've used:

$getMaxValue  = $this->db->query('SELECT 1 + coalesce((SELECT MAX(image_Group_Id)), 0) AS image_Group_Id FROM mg_gallery');
if($getMaxValue->num_rows() > 0){
    $group_Id    = $getMaxValue->row_array();
    $image_Group_Id  = $group_Id['image_Group_Id'];
}else{
    $image_Group_Id  = 0;
}

foreach($_POST['image_Basename'] as $key=>$image_Basename){
    $image_Title = $this->input->post('image_Title');
    $image_Category_Id = $this->input->post('image_Category_Id');
    $this->db->query("INSERT INTO mg_gallery (image_title, image_Basename, image_Category_Id, image_Group_Id)
                      VALUES ('$image_Title', '$image_Basename', '$image_Category_Id', $image_Group_Id)
    ");
}