SQL使2種不同的日期類型在一個查詢

Question

我做了有3個表的查詢：1當年，去年和名稱的國家

的正如你可以看到當年和最後的結果一年是一樣的，這是這裏的問題。我想用喜歡。我想用一個當前年份和去年一個查詢進行查詢。

我可以用這個去年YEAR(o.date_add) = YEAR(NOW() - INTERVAL 1 YEAR)

而且從目前的一年，我可以用這個例子：YEAR(o.date_add) = YEAR(CURRENT_DATE())

我的查詢：

SELECT 
    IFNULL(SUM(DISTINCT o.total_paid_tax_excl), 0) AS CurrentYEAR, 
    IFNULL(SUM(DISTINCT o.total_paid_tax_excl), 0) AS LastYEAR, 
    IFNULL(CONCAT(l.name), 0) AS name 
FROM 
    expoled.ps_orders o 
     LEFT JOIN 
    expoled.ps_address a ON o.id_address_delivery = a.id_address 
     INNER JOIN 
    expoled.ps_country c ON a.id_country = c.id_country 
     INNER JOIN 
    expoled.ps_country_lang l ON c.id_country = l.id_country 
WHERE 
    l.id_lang = 7 
     AND o.current_state IN (3 , 4, 5, 9, 13, 15, 20, 22, 23, 24, 25, 121) 
     AND l.name NOT IN ('Netherlands') 
GROUP BY (l.name) 

我可以做，但我想單獨查詢它在1查詢我怎麼能​​這個？ 我嘗試過聯盟，但結果保持不變。

我想有像這樣（這一個不工作！只是舉例[Photoshop中]

---

我想我需要更改查詢的這部分

SELECT 
    IFNULL(SUM(o.total_paid_tax_excl), 0) AS CurrentYEAR, 
    IFNULL(SUM(o.total_paid_tax_excl), 0) AS LastYEAR, 
    IFNULL(CONCAT(l.name), 0) AS name 
FROM 

這添加到我的查詢

對於CurrentYEAR = YEAR(o.date_add) = YEAR(CURRENT_DATE())

對於LastYEAR = YEAR(o.date_add) = YEAR(NOW() - INTERVAL 1 YEAR)

Answer 1

可以使用sum()聚合函數內的條件表達式（if()功能或case語句）添加只有那些符合標準值：

SELECT 
    IFNULL(SUM(DISTINCT if(YEAR(o.date_add) = YEAR(CURRENT_DATE()),o.total_paid_tax_excl, 0)), 0) AS CurrentYEAR, 
    IFNULL(SUM(DISTINCT if(YEAR(o.date_add) = YEAR(CURRENT_DATE())-1,o.total_paid_tax_excl, 0)), 0) AS LastYEAR, 
    IFNULL(l.name, '') AS name 
FROM 
    expoled.ps_orders o 
     LEFT JOIN 
    expoled.ps_address a ON o.id_address_delivery = a.id_address 
     INNER JOIN 
    expoled.ps_country c ON a.id_country = c.id_country 
     INNER JOIN 
    expoled.ps_country_lang l ON c.id_country = l.id_country 
WHERE 
    l.id_lang = 7 
     AND o.current_state IN (3 , 4, 5, 9, 13, 15, 20, 22, 23, 24, 25, 121) 
     AND l.name NOT IN ('Netherlands') 
GROUP BY IFNULL(l.name, '') 

我還簡化了表達爲名稱字段，並使group by子句與它一致。

我沒有更改查詢的任何其他部分，但我並不完全同意sum()中的distinct，因爲您可以使用與納稅相同的價值，但這是您的數據。

如果您的表的數據比前一年的數據要舊，那麼請考慮添加where條件來限制運行計算的記錄。

Answer 2

我想你可以嘗試這樣的事情（我加CASE與SUM場和一個WHERE條件只提取相關年份）：

SELECT 
    IFNULL(SUM( CASE WHEN YEAR(CURRENT_DATE)-YEAR(o.date_date) =0 THEN o.total_paid_tax_excl ELSE 0 END), 0) AS CurrentYEAR, 
    IFNULL(SUM(CASE WHEN YEAR(CURRENT_DATE)-YEAR(o.date_date) =1 THEN o.total_paid_tax_excl ELSE 0 END), 0) AS LastYEAR, 
    IFNULL(CONCAT(l.name), 0) AS name 
FROM 
    expoled.ps_orders o 
     LEFT JOIN 
    expoled.ps_address a ON o.id_address_delivery = a.id_address 
     INNER JOIN 
    expoled.ps_country c ON a.id_country = c.id_country 
     INNER JOIN 
    expoled.ps_country_lang l ON c.id_country = l.id_country 
WHERE 
    l.id_lang = 7 
     AND o.current_state IN (3 , 4, 5, 9, 13, 15, 20, 22, 23, 24, 25, 121) 
     AND l.name NOT IN ('Netherlands') 
     AND YEAR(o.date_date) IN (YEAR(CURRENT_DATE()), YEAR(CURRENT_DATE)-1) 
GROUP BY (l.name)