如何優先考慮工會中未過期的帖子

Question

「要約」類型的期限爲1或0，「清算」類型的截止日期爲截止日期。當他們沒有過期時，我怎樣才能在查詢中給予他們更多的權重？

（搜索頁面）的當前查詢：

SELECT 
    'offer' AS type, 
    id, 
    expired, 
    title, 
    description, 
    header, 
    slug, 
    date_original, 
    date 
FROM cs_offers 
WHERE MATCH(title,title,description,keywords,header,country,offer_description) AGAINST ('$search_main' IN BOOLEAN MODE) 

    UNION 

SELECT 
    'sweep' AS type, 
    id, 
    title, 
    description, 
    header, 
    expire_date, 
    slug, 
    date_original, 
    date_original AS date 
FROM cs_sweeps 
WHERE MATCH(title,title,description,keywords,header,category,location,entry_type,country,w) AGAINST ('$search_main' IN BOOLEAN MODE) 

    UNION 

SELECT 
    'video' AS type, 
    id, 
    id AS id2, 
    title, 
    description, 
    keywords, 
    slug, 
    date_original, 
    date 
FROM cs_vlog 
WHERE MATCH(title,title,description,keywords,video_description) AGAINST ('$search_main' IN BOOLEAN MODE) 


    UNION 

SELECT 
    'post' AS type, 
    id, 
    id AS id2, 
    title, 
    description, 
    header, 
    slug, 
    date_original, 
    date 
FROM cs_blog 
WHERE MATCH(title,title,description,keywords,header,body) AGAINST ('$search_main' IN BOOLEAN MODE) 
ORDER BY date DESC 

換句話說，如何才能讓當前所有帖子首先在查詢？

Answer 1

對於每一個工會的一部分創建一個虛擬列expired，然後通過order by expired asc, date desc訂購您的整個聯盟：

(select ..., expired from offer ...) 
union all 
(select ..., expire_date < now() as expired from sweep ...) 
... 
order by expired asc, date desc 

括號是非常重要的。還要確保每個聯合部分的列數和順序是相同的。