按問題分組的普遍查詢

Question

我正在嘗試在普及數據庫上運行此查詢

select cust_no,cust_name,sum(bvtotal) as Amount
from sales_history_header  
where cust_no is not null and number is not null and bvtotal > 1000 and in_date < 20140101
group by cust_no,cust_name
order by sum(bvtotal) desc;

如何排除子結果中in_date> 20140101的組結果？

我也有此查詢正在獲取in_date> 20140101的那些結果

難道我做錯了什么 ？

我得到的樣本輸出是這種格式

cust_no     cust_name      amount
A             a1            500
B             b1            500
C             c1            1000

我想使用cust_no'A'排除此記錄，因為它在20140202中具有與in_date的事務

考慮在我的原始數據中，我有類似的記錄

cust_no     cust_name      amount    in_date
A             a1            100      20130203
A             a1            400      20130101
A             a1            1000     20140503

Answer 1

您需要根據一組ID排除所有記錄。 通常，您可以使用子查詢來執行此操作：

SELECT cust_no,
    cust_name,
    sum(bvtotal) AS Amount
FROM sales_history_header
WHERE cust_no IS NOT NULL
    AND number IS NOT NULL
    AND bvtotal > 1000
    AND cust_no NOT IN (
        SELECT cust_no 
        FROM sales_history_header 
        WHERE in_date >= 20140101 
            AND cust_no IS NOT NULL
    )
GROUP BY cust_no,
    cust_name
ORDER BY sum(bvtotal) DESC;

子查詢的AND cust_no IS NOT NULL部分是為了避免NOT IN和NULL值出現問題。 如果將其重寫為NOT EXISTS相關子查詢，則可能會獲得更好的性能，但以我的經驗，MySQL在這些方面相當糟糕。

另一種選擇是更明確的自我防聯接方法（LEFT JOIN和filter，其中右表為null），但這有點...粗略的感覺？...因為您似乎允許cust_no為NULL並且它是一個查詢正在聚合，因此感覺就像您不得不擔心會增加行：

SELECT s1.cust_no,
    s1.cust_name,
    sum(s1.bvtotal) AS Amount
FROM sales_history_header s1
LEFT JOIN (
        SELECT cust_no
        FROM sales_history_header
        WHERE cust_no IS NOT NULL
            AND number IS NOT NULL
            AND bvtotal > 1000
            AND in_date >= 20140101) s2
    ON  s2.cust_no = s1.cust_no
WHERE s1.cust_no IS NOT NULL
    AND s1.number IS NOT NULL
    AND s1.bvtotal > 1000
    AND s2.cust_no IS NULL
GROUP BY cust_no,
    cust_name
ORDER BY sum(bvtotal) DESC;

WHERE [...] s2.cust_no IS NULL LEFT JOIN與WHERE [...] s2.cust_no IS NULL組合在一起，可以消除不需要的記錄。

Answer 2

我認為您需要將日期常數指定為日期，除非您確實要處理整數。

select cust_no,cust_name,sum(bvtotal) as Amount
from sales_history_header  
where cust_no is not null and number is not null and bvtotal > 1000 and in_date < '2014-01-01'
group by cust_no,cust_name
order by sum(bvtotal) desc;

Answer 3

我不明白你到底需要什么

但是似乎您混合了INT和DATE類型。

因此，如果您的in_date字段的類型為DATE

select 
  cust_no,
  cust_name,
  sum(bvtotal) as Amount
from sales_history_header  
where cust_no is not null 
  and number is not null 
  and bvtotal > 1000 
  and in_date < DATE('2014-01-01')
group by cust_no,cust_name
order by sum(bvtotal) desc;

如果您的in_date字段鍵入TIMESTAMP

select 
  cust_no,
  cust_name,
  sum(bvtotal) as Amount
from sales_history_header  
where cust_no is not null 
  and number is not null 
  and bvtotal > 1000 
  and in_date < TIMESTAMP('2014-01-01 00:00:00')
group by cust_no,cust_name
order by sum(bvtotal) desc;