从数组中删除重复值

Posted 2023-02-24

【中文标题】从数组中删除重复值

【英文标题】：Removes duplicate values from an array

【发布时间】：2014-10-10 09:38:39

【问题描述】：

我有一个使用 mysql 的 CodeIgniter 生成的数组。 [co_name] => 中的值是重复的，我尝试使用 co_id 对它进行 group_by 它不起作用，但它也使用 group_by 使用 group_by.CodeIgniter group_by 仅适用于一个 group_by 或任何从[co_name] =>删除重复值的其他方法。

Array
(
    [0] => stdClass Object
        (
            [order_date] => 1408255199
            [cus_id] => 6
            [order_deliver_name] => Jankia
            [order_deliver_add_no] => 5085
            [order_deliver_add_street] => mapanawathura road
            [order_deliver_add_city] => Kandy
            [order_deliver_contact] => 0716352632
            [order_deliver_date] => 2014-08-12
            [order_status] => pending
            [emp_id] => 
            [cmp_name] => Burger Bun 
            [co_name] => Put Ham 
Put Tomato 
Put Ham 
Put Tomato 
Put Chilli Sauce 
Put Tomato 
Put Chilli Sauce 
Put Ham 
Put Chilli Sauce 
            [order_id] => 28
            [quantity] => 10
        )

这是我的代码

function get_customize_orders()

        $this->db->select(array(

            'tbl_order_product_details.order_date',
            'tbl_order_product_details.cus_id',
            'tbl_order_product_details.order_deliver_name',
            'tbl_order_product_details.order_deliver_add_no',
            'tbl_order_product_details.order_deliver_add_street',
            'tbl_order_product_details.order_deliver_add_city',
            'tbl_order_product_details.order_deliver_contact',
            'tbl_order_product_details.order_deliver_date',
            'tbl_order_product_details.order_status',
            'tbl_order_product_details.emp_id',
            'tbl_customise_main_product.cmp_name',
            'GROUP_CONCAT(tbl_customise_optional.co_name SEPARATOR "<br />" ) as co_name ',
            'tbl_order_products.order_id',
            'tbl_order_products.quantity',
        ));
        $this->db->from('tbl_order_products');
        $this->db->join('tbl_customise_join_products', 'tbl_customise_join_products.cmp_id=tbl_order_products.product_id');
        $this->db->join('tbl_customise_main_product', 'tbl_customise_main_product.cmp_id=tbl_customise_join_products.cmp_id');
        $this->db->join('tbl_customise_order_products', 'tbl_customise_order_products.order_id=tbl_order_products.order_id');
        $this->db->join('tbl_customise_optional', 'tbl_customise_optional.co_id=tbl_customise_order_products.co_id');
        $this->db->join('tbl_order_product_details', 'tbl_order_product_details.order_id=tbl_order_products.order_id');
        $this->db->group_by('tbl_order_products.order_id');
        $query = $this->db->get();
        return $query->result();

    

【参考方案1】：

在GROUP_CONCAT 中使用DISTINCT，这样它只会连接每个order_id 组中不同的co_name

GROUP_CONCAT(DISTINCT tbl_customise_optional.co_name SEPARATOR "<br />" ) as co_name