How to check if row exists on database CodeIgniter - php

Question

So I'm having a bit of troubles with this query as it is the first time in which instead of checking for a value in a row, I'm checking if a row itself exists on database.
This is the problem that I'm facing:
UPDATE:
public function individualDiscountVerification($id){
// Get postID
$data['item'] = $this->PublicStore_model->readPostID($id);
$data['relationship'] = $this->PublicStore_model->getPostRelationship($id);
// Get Last Post ID
$postID = $id;
$activityTitle = $data['item']->title;
// Verify Data
$itemInCart = $this->PublicCart_model->verifyUserCartItem($postID);
// Redirect if row does not exist -- HERE IS WHERE I NEED HELP
if(!$itemInCart){
// Set message
$this->session->set_flashdata('error', 'You first need to add it to you cart');
// Redirect
redirect('store/read/'.$id);
// Redirect if seller is the same as the current userID
} elseif($this->session->userdata('user_id') == $data['relationship']->user_id) {
// Set message
$this->session->set_flashdata('error', 'You can not add discounts to your own products');
// Redirect
redirect('store/read/'.$id);
} else {
// Verify discount exists
$discount = $this->input->post('discount_code');
$discountCode = $this->PublicCart_model->verifySingleDiscount($discount);
if(!$discountCode){
// Set message
$this->session->set_flashdata('error', 'The discount has expired or is invalid');
// Redirect
redirect('store/read/'.$id);
} else {
// Get Last ID Data
$discountID = $discountCode->discount_id;
// Get Discount Type
$discountType = $this->PublicCart_model->getIndividualDiscountID($discountID);
// Verify data
$verifyItemDiscount = $this->PublicCart_model->verifySingleItemDiscountCode($postID, $discountID);
if($discountType->type == 'percent' && $verifyItemDiscount != NULL?:'' && $discountID == $data['relationship']->discount_id){
// Update Post Array
$postData = array(
'price' => round($data['relationship']->price * ((100 - $discountCode->amount) / 100), 2),
'discount_id' => $discountID,
);
// Update Post Array
$this->PublicCart_model->updateUserCartItem($postID, $postData);
// Set message
$this->session->set_flashdata('success', 'A percent discount type has been applied to your final price');
// Redirect
redirect('store/read/'.$data['item']->post_id);
} elseif($discountID != $data['relationship']->discount_id){
// Set message
$this->session->set_flashdata('error', 'Percent discount is not attached to this product');
// Redirect
redirect('store/read/'.$data['item']->post_id);
} elseif($discountType->type == 'float' && $verifyItemDiscount != NULL?:'' && $discountID == $data['relationship']->discount_id){
// Update Post Array
$originalprice = $data['relationship']->price;
$amount = $discountCode->amount;
$postData = array(
'price' => $originalprice - $amount,
'discount_id' => $discountID,
);
// Update Post Array
$this->PublicCart_model->updateUserCartItem($postID, $postData);
// Set message
$this->session->set_flashdata('success', 'A float discount type has been applied to your final price');
// Redirect
redirect('store/read/'.$data['item']->post_id);
} elseif($discountID != $data['relationship']->discount_id){
// Set message
$this->session->set_flashdata('error', 'Float discount is not attached to this product');
// Redirect
redirect('store/read/'.$data['item']->post_id);
}
// Activity Array
$activityData = array();
// Insert Activity
$this->Activity_model->add($activityData);
}
}
}
and here is the method in the model:
UPDATE:
/*
*
* IS IN USER'S CART? -- FROM HERE AND BELOW IS FOR THE INDIVIDUAL ITEMS DISCOUNT
*
*/
public function verifyUserCartItem($postID){
$query = $this->db->get($this->relationship, array(
'post_id' => $postID,
'friend_id' => $this->session->userdata('user_id'),
'type' => $this->cartType,
));
if($query->num_rows() > 0){
return $query->row_array();
} else {
return null;
}
}
/*
*
* DOES THE DISCOUNT EXISTS?; IF YES, WHAT TYPE OF DISCOUNT IT IS?
*
*/
public function verifySingleDiscount($discount){
$query = $this->db->get_where($this->discounts, array(
'code' => $discount,
));
return $query->row();
}
public function getIndividualDiscountID($discountID){
$query = $this->db->get_where($this->relationship, array(
'discount_id' => $discountID,
'status' => $this->published,
));
return $query->row();
}
/*
*
* IS THE DISCOUNT ATTACHED TO THE POST?; IF YES, UPDATE IT
*
*/
public function verifySingleItemDiscountCode($postID, $discountID){
$query = $this->db->get_where($this->relationship, array(
'post_id' => $postID,
'discount_id' => $discountID,
'status' => $this->published,
));
return $query->row();
}
public function updateUserCartItem($postID, $postData){
$this->db->select('*');
$this->db->where('friend_id', $this->session->userdata('user_id'));
$this->db->where('post_id', $postID);
$this->db->where('type', $this->cartType);
$this->db->update($this->relationship, $postData);
}
Note: As you can see I'm already using isset but that messes up the following blocks of code(I'll put the whole function if requested) which are not posted here; I already used if empty or if var === false but I'm still getting the same error.

Answer 1

try below in verifyUserCartItem function :
if($query->num_rows() > 0){
return $query->row_array();
} else {
return null;
}
and if(!$itemInCart){ instead of if(isset($itemInCart)){

Answer 2

For example:
var_dump($this->db->where('id', $id)->get('TABLE_NAME')->num_rows());