Question

我需要将以下在SQL Server中执行的查询转换为Oracle。

SELECT 
    LABEL_A, LABEL_B, 
    CASE
        WHEN IS_C = '0' AND IS_B = 'S' THEN 'L1'
        WHEN IS_C = '1' AND IS_B = 'B' THEN 'L1'
        WHEN IS_C = '0' AND IS_B = 'B' THEN 'L2'
        WHEN IS_C = '1' AND IS_B = 'S' THEN 'L2'
    END AS L,
    QTY
FROM
    DATA
WHERE 
    PRICE > 0 AND E_DATE >= getdate()-1) AS LS
GROUP BY 
    LABEL_A, LABEL_B, L
HAVING 
    SUM(QTY/100) >= 150

你能帮我吗？

感谢。

Answer 1

大多数错误都在这一行：

WHERE PRICE > 0 AND E_DATE] >= getdate()-1) AS LS

您有额外的]和)个字符，getdate()被SYSDATE取代，您需要删除该行末尾的别名。除此之外，您不能在GROUP BY子句中使用列别名，并且需要使用整个case语句（或将其包装在子查询中）。

您还遇到QTY不属于GROUP BY子句的问题。

SELECT LABEL_A,
       LABEL_B, 
       CASE
         WHEN IS_C = '0' AND IS_B = 'S' THEN 'L1'
         WHEN IS_C = '1' AND IS_B = 'B' THEN 'L1'
         WHEN IS_C = '0' AND IS_B = 'B' THEN 'L2'
         WHEN IS_C = '1' AND IS_B = 'S' THEN 'L2'
       END AS L,
       SUM( QTY ) AS QTY
FROM   DATA
WHERE  PRICE > 0
AND    E_DATE >= SYSDATE-1
GROUP BY
       LABEL_A,
       LABEL_B,
       CASE
         WHEN IS_C = '0' AND IS_B = 'S' THEN 'L1'
         WHEN IS_C = '1' AND IS_B = 'B' THEN 'L1'
         WHEN IS_C = '0' AND IS_B = 'B' THEN 'L2'
         WHEN IS_C = '1' AND IS_B = 'S' THEN 'L2'
       END
HAVING SUM(QTY/100) >= 150

Answer 2

从SQL Server移植到Oracle的主要挑战是后者不允许在SELECT子句中使用GROUP BY语句中的别名。但是，我们可以使用子查询来重用它，而不是重复冗长的CASE表达式。

SELECT t.LABEL_A,
       t.LABEL_B,
       t.L,
       SUM(t.QTY) AS QTY
FROM
(
    SELECT LABEL_A,
           LABEL_B, 
           CASE WHEN IS_C = '0' AND IS_B = 'S' THEN 'L1'
                WHEN IS_C = '1' AND IS_B = 'B' THEN 'L1'
                WHEN IS_C = '0' AND IS_B = 'B' THEN 'L2'
                WHEN IS_C = '1' AND IS_B = 'S' THEN 'L2'
           END AS L,
           QTY
    FROM DATA
    WHERE PRICE > 0 AND E_DATE >= SYSDATE - 1
) t
GROUP BY t.LABEL_A, t.LABEL_B, t.L
HAVING SUM(t.QTY)/100 >= 150

Answer 3

在这一行：

WHERE PRICE > 0 AND E_DATE] >= getdate()-1) AS LS

删除此处]和)（在MS中似乎也无效）并将getDate()替换为sysdate。休息应该没问题，除了group by需要用L语句替换CASE。

SQL查询中的计算字段值

3 个答案: