Php 在插入数据之前，检查具有条件的特定列的总和

我需要帮助！我只想从用户处插入数据，但在此之前，它将首先检查数据库中的“dami”列是否为您使用的

SELECT

是错误的。这是路

public function do_create_businesscard($txttelno,$txttelno1,$txtfaxno,$txtmobileno,$txtmobileno1,$txtemail,$txtemail1,$txtPieces,$is_deleted)
{
    $sql = "SELECT SUM(dami) FROM tbl_business_card_information WHERE is_deleted = 1";
    $result = $this->db->query($sql);
    $row = $result->fetch_array(MYSQLI_NUM);
    $total = $row[0];
    if ($total > 100){
        echo "Sorry but you already reach you maximum request";
    }else{
        $sql = "INSERT INTO tbl_business_card_information (`tel_no`,`tel_no1`,`fax_no`,`mobile_no`,`mobile_no1`,`email`,`email1`,`dami`) VALUES (?,?,?,?,?,?,?,?)";

        $data = array($txttelno,$txttelno1,$txtfaxno,$txtmobileno,$txtmobileno1,$txtemail,$txtemail1,$txtPieces);                           
        $query = $this->db->query($sql,$data);
        return $query;  
    }
}

public function do_create_businesscard($txttelno,$txttelno1,$txtfaxno,$txtmobileno,$txtmobileno1,$txtemail,$txtemail1,$txtPieces,$is_deleted)
{
    $sql = "SELECT SUM(dami) FROM tbl_business_card_information WHERE is_deleted = 1";
    $result = $this->db->query($sql);
    $row = $result->fetch_array(MYSQLI_NUM);
    $total = $row[0];
    if ($total > 100){
        echo "Sorry but you already reach you maximum request";
    }else{
        $sql = "INSERT INTO tbl_business_card_information (`tel_no`,`tel_no1`,`fax_no`,`mobile_no`,`mobile_no1`,`email`,`email1`,`dami`) VALUES (?,?,?,?,?,?,?,?)";

        $data = array($txttelno,$txttelno1,$txtfaxno,$txtmobileno,$txtmobileno1,$txtemail,$txtemail1,$txtPieces);                           
        $query = $this->db->query($sql,$data);
        return $query;  
    }
}