聯盟 - 同桌，不包括前面的結果的MySQL

Question

我想寫一個查詢，將：

• 運行查詢，給我（x）的行數（上限4）
• 如果查詢沒有給我4我的需要，運行第二個查詢限制4-（x）和第一個查詢
• 排除IDS，它如同第二

我有這方面的一個第三個查詢：

(SELECT *, 1 as SORY_QUERY1 FROM xbamZ where state = 'Minnesota' and industry = 'Miscellaneous' and id != '229' limit 4) 
UNION 
(SELECT *, 2 FROM xbamZ where state = 'Minnesota' limit 2) 
UNION 
(SELECT *, 3 FROM xbamZ where industry = 'Miscellaneous' limit 1) 

我該怎麼做（或者是？）？我關門了嗎？此查詢給我重複

Answer 1

我認爲不需要聯合和三個select s。一個也會工作

SELECT a.* 
FROM 
(
SELECT xbamZ.*, 
CASE 
    WHEN state = 'Minnesota' and industry = 'Miscellaneous' and id != '229' THEN 1 
    WHEN state = 'Minnesota' THEN 2 
    WHEN industry = 'Miscellaneous' THEN 3 
END as rnk 
FROM xbamZ 
where state = 'Minnesota' or industry = 'Miscellaneous' 
)a 
ORDER BY rnk 
LIMIT 4;