Question

我需要按年份对数据进行并排比较。

我正在使用Microsoft Access 2013。

我想要获得的是这样的表：

╔══════╦══════════╦ ... ╦═══════╦═══════════════╦══════════════╦════════════╗
║ Zone ║ Customer ║ ... ║ Month ║ Previous year ║ Current year ║ Difference ║
╠══════╬══════════╬ ... ╬═══════╬═══════════════╬══════════════╬════════════╣
║ PD   ║ A        ║ ... ║     1 ║ 100€          ║ 150€         ║ +50€       ║
║ PD   ║ B        ║ ... ║     2 ║ 150€          ║ 100€         ║ -50€       ║
║ PD   ║ C        ║ ... ║     1 ║ 200€          ║ 0€           ║ -200€      ║
║ PD   ║ D        ║ ... ║     2 ║ 0€            ║ 100€         ║ +100€      ║
╚══════╩══════════╩ ... ╩═══════╩═══════════════╩══════════════╩════════════╝

("..." stands for other columns)

确定前一年是2014年，当前是2015年，通过此表我可以看到：

2014年客户已在2015年（客户A）购买更多;
2014年客户已在2015年（客户B）购买更少;
2015年客户尚未购买（客户C）;
2015年有新客户（客户D）。

当我有一个2015年没有购买的“旧”（2014）客户时我需要在“当前年度”栏目（2015年）中看到“0€”值的那一行等等同样对于2015年的新客户来说，显然在2014年没有购买任何东西。

这些是我的表格：

CUSTOMERS（id，company_name，id_zone，id_customer_category）
CUSTOMER_CATEGORIES（id，description）
ORDERS（id，id_customer，date，qty，amount（€），id_product_category， id_import）
PRODUCT_CATEGORIES（id，supplier，description）
ZONES（id，city）
进口（id，年，月，供应商）

我创建了一个视图（ V_YEAR_SALES ）：

SELECT Z.ID AS ID_ZONE, Z.CITY, C.COMPANY_NAME AS CUSTOMER, CAT.DESCRIPTION AS CUSTOMER_CATEGORY, P.SUPPLIER, P.DESCRIPTION AS PRODUCT_CATEGORY, I.MONTH, I.YEAR, SUM(O.AMOUNT) AS AMOUNT
FROM ((((ORDERS AS O 
    INNER JOIN CUSTOMERS AS C ON O.ID_CUSTOMER = C.ID) 
    INNER JOIN ZONES AS Z ON Z.ID = C.ID_ZONE) 
    INNER JOIN IMPORTS AS I ON I.ID = O.ID_IMPORT) 
    INNER JOIN CUSTOMER_CATEGORIES AS CAT ON CAT.ID = C.ID_CUSTOMER_CATEGORY)
    INNER JOIN PRODUCT_CATEGORIES AS P ON O.ID_PRODUCT_CATEGORY = P.ID
GROUP BY Z.ID, Z.CITY, C.COMPANY_NAME, CAT.DESCRIPTION, P.SUPPLIER, P.DESCRIPTION, I.MONTH, I.YEAR
ORDER BY Z.CITY, P.SUPPLIER, P.DESCRIPTION, CAT.DESCRIPTION, C.COMPANY_NAME, I.YEAR, I.MONTH;

每次我需要在一年和上一年之间进行比较时，我会使用此视图（ V_SALES_COMPARISON ）来传递年份：

SELECT S1.ID_ZONE, S1.CITY, S1.ID_CUSTOMER, S1.CUSTOMER, S1.ID_CUSTOMER_CATEGORY, S1.CUSTOMER_CATEGORY, S1.SUPPLIER, S1.ID_PRODUCT_CATEGORY, S1.PRODUCT_CATEGORY, S1.YEAR, S1.MONTH, S1.AMOUNT AS CURRENT_YEAR, S2.AMOUNT AS PREVIOUS_YEAR, S1.AMOUNT - S2.AMOUNT AS DIFFERENCE
FROM 
    (SELECT * FROM V_YEAR_SALES) AS S1 
    LEFT JOIN 
    (SELECT * FROM V_YEAR_SALES) AS S2 
        ON (S1.ID_ZONE = S2.ID_ZONE) 
        AND (S1.SUPPLIER = S2.SUPPLIER) 
        AND (S1.ID_PRODUCT_CATEGORY = S2.ID_PRODUCT_CATEGORY) 
        AND (S1.ID_CUSTOMER_CATEGORY = S2.ID_CUSTOMER_CATEGORY) 
        AND (S1.ID_CUSTOMER = S2.ID_CUSTOMER) 
        AND (S1.YEAR = S2.YEAR + 1) 
        AND (S1.MONTH = S2.MONTH);

参考上述所需结果表，使用此视图，我只能获得客户A，B，D 但不是C 的行！

我需要包括2014年尚未购买的客户！

我正在使用JOIN，但我不知道这是否是最佳方法。也许我可以使用PIVOTING，但我不知道是否以及如何使用Access实现。

Answer 1

你可以这样：

SELECT 
    Customer, 
    Sum(IIf(DateDiff("yyyy",[InvoiceDate],Date())=1,[Amount],0)) AS LastYear, 
    Sum(IIf(DateDiff("yyyy",[InvoiceDate],Date())=0,[Amount],0)) AS ThisYear, 
    Sum(IIf(DateDiff("yyyy",[InvoiceDate],Date())=0,[Amount],0)) 
       - Sum(IIf(DateDiff("yyyy",[InvoiceDate],Date())=1,[Amount],0)) AS Diff
FROM 
    Invoices
GROUP BY 
    Customer;

我看到你有一个单独的年份字段，所以试试这个方法：

SELECT 
    Customer, 
    Sum(IIf(Year(Date())-[YearField]=1,[Amount],0)) AS LastYear, 
    Sum(IIf(Year(Date())-[YearField]=0,[Amount],0)) AS ThisYear, 
    Sum(IIf(Year(Date())-[YearField]=0,[Amount],0)) 
       - Sum(IIf(Year(Date())-[YearField]=1,[Amount],0)) AS Diff
FROM 
    Invoices
GROUP BY 
    Customer;

Answer 2

最后，我使用 PIVOTING 找到了解决方案。

V_YEAR_SALES 视图已替换为：

TRANSFORM
IIF(SUM(O.AMOUNT) IS NULL, 0, SUM(O.AMOUNT))
SELECT Z.ID AS ID_ZONE, Z.CITY, C.COMPANY_NAME AS CUSTOMER, CAT.DESCRIPTION AS CUSTOMER_CATEGORY, P.SUPPLIER, P.DESCRIPTION AS PRODUCT_CATEGORY, I.MONTH, I.YEAR
FROM ((((ORDERS AS O 
    INNER JOIN CUSTOMERS AS C ON O.ID_CUSTOMER = C.ID) 
    INNER JOIN ZONES AS Z ON Z.ID = C.ID_ZONE) 
    INNER JOIN IMPORTS AS I ON I.ID = O.ID_IMPORT) 
    INNER JOIN CUSTOMER_CATEGORIES AS CAT ON CAT.ID = C.ID_CUSTOMER_CATEGORY)
    INNER JOIN PRODUCT_CATEGORIES AS P ON O.ID_PRODUCT_CATEGORY = P.ID
WHERE I.YEAR BETWEEN 
    (SELECT MAX(YEAR) FROM IMPORTS) AND (SELECT MAX(YEAR)-3 FROM IMPORTS)
GROUP BY Z.ID, Z.CITY, C.COMPANY_NAME, CAT.DESCRIPTION, P.SUPPLIER, P.DESCRIPTION, I.MONTH, I.YEAR

V_SALES_COMPARISON视图已删除，因为不再需要了。我的查询现在仅适用于V_YEAR_SALES。

查询新V_YEAR_SALES 更快 <{1}}。

如果您需要从Access或不带参数查询视图：

V_SALES_COMPARISON

相反，如果您需要使用Jet Driver从代码查询视图，并且您还想使用参数，则需要执行以下操作：

SELECT S.*
FROM V_YEAR_SALES AS S
WHERE S.YEAR IN (2015, 2014) AND S.MONTH BETWEEN 1 AND 12;

要小心要包含PARAMETERS P0 TEXT(255), P1 TEXT(255), P2 TEXT(255), P3 TEXT(255); SELECT S.* FROM V_YEAR_SALES AS S WHERE S.YEAR IN (@P0, @P1) AND S.MONTH BETWEEN @P2 AND @P3;声明（PARAMETERS声明之前还有;），否则你会从Jet Driver收到错误：

SELECT

使用Access在SQL中按年份进行数据比较

2 个答案: