MySQL 按字段排序（column_name，子查询）

Question

我正在尝试获取数据以显示如下内容：

数据库模式：

category_id	parent_category
banana	fruit
apple	fruit
kiwi	fruit
cucumber	vegetable
celery	vegetable
pork	meat
beef	meat
chicken	meat
t-shirt	clothes
jeans	clothes
sweater	clothes
meat	food
fruit	food
vegetable	food
food	null
clothes	null

select * from category 
order by 
field(category_id, "banana") desc,
field(parent_category, (SELECT parent_category FROM category WHERE category_id = "banana")) desc
field(category_id, (select category_id from category where parent_category <> (SELECT parent_category FROM category WHERE category_id = "banana"))) desc

我的目标结果是按以下顺序显示：
香蕉第一，
其他种类的水果其次，
其他种类的食物第三，
最后穿衣服（所有其他不被视为食物的数据。）
第二级和第三级类别不必显示（肉类、水果、蔬菜、T 恤、牛仔裤、毛衣、食品、衣服）

Answer 1

也许是这样的：

SELECT * FROM category 
 WHERE 
    IF(parent_category='food',NULL,parent_category) IS NOT NULL
ORDER BY
   CASE WHEN category_id='banana' THEN 1
        WHEN parent_category='fruit' THEN 2
        WHEN parent_category='clothes' THEN 99
        ELSE 3 END;

在 ORDER BY 部分使用 CASE 表达式并过滤掉 parent_category 即 food 和 NULL。结果将是这样的：

category_id	parent_category
banana	fruit
apple	fruit
kiwi	fruit
cucumber	vegetable
celery	vegetable
pork	meat
beef	meat
chicken	meat
t-shirt	clothes
jeans	clothes
sweater	clothes

Demo fiddle

MySQL 按字段排序（column_name，子查询）

MySQL order by field(column_name, subquery)

mysql

sql

sql-order-by