我正在创建一个搜索查询mysql，使用 UNION 要连接多个表，现在的问题是添加别名来标识每个表，因为如果添加带有别名的表名，则会显示错误 COLUMN NOT FOUND 我试图在每个联合表上添加别名，但遇到了错误，我不知道该怎么做才能将其写入。有人能帮我吗。
查询

SELECT * FROM (
    (
        SELECT 'food' as type,
        food_id AS item_id,
        food_name AS item_name,
        primary_image AS item_img,
        food_price AS item_price,
        food_currency AS item_currency,
        food_discount AS item_discount,
        chef_status AS ison
        FROM foods
    ) AS f

    UNION

    (
        SELECT 'chef' as type,
        chef_pagename AS item_id,
        business_name AS item_name,
        chef_photo AS item_img,
        NULL AS item_price,
        NULL AS item_currency,
        NULL AS item_discount,
        chef_status AS ison
        FROM our_chefs
    ) AS c
) AS fsc

WHERE f.food_name LIKE '%chicken%'
OR f.item_price LIKE '%100%'
OR c.business_name LIKE '%chicken%'
AND fsc.ison = 1

谢谢你们的贡献，我现在已经解决了这个问题

WHERE item_name LIKE '%chicken%'
OR item_price LIKE '%100%'
AND fsc.ison = 1