Question

如何填补行间的间隙？我使用表日历，但我的查询似乎不正确。结果没有显示差距..

SELECT calendar.datefield, t2.*
    FROM store_relation t1,store t3, store_product t2
            RIGHT JOIN calendar ON (DATE(t2.created) = calendar.datefield)
            WHERE (calendar.datefield BETWEEN ('2012-07-15') and ('2012-07-20'))
    AND t1.id_store_a = 1
    AND t1.id_store_b = t2.id_store
    AND t3.id = t2.id_store
    AND t2.id_product = 11
    ORDER By t2.price

结果：

datefield   |   id_product   |   id_store   |   created
2012-07-15      1                1              2012-07-15
2012-07-18      1                1              2012-07-18
2012-07-20      1                1              2012-07-20
2012-07-20      1                1              2012-07-20

我在等待结果

datefield   |   id_product   |   id_store   |   created
2012-07-15      1                1              2012-07-15
2012-07-16      null             null           null
2012-07-17      null             null           null
2012-07-18      1                1              2012-07-18
2012-07-19      null             null           null
2012-07-20      1                1              2012-07-20
2012-07-20      1                1              2012-07-20

Answer 1

如果您有LEFT / RIGHT JOIN并且您正在筛选可选的表，那么WHERE子句将保留这些记录。您需要包含一个条件，允许RIGHT JOIN的左侧部分丢失：

WHERE (calendar.datefield BETWEEN ('2012-07-15') and ('2012-07-20'))
AND
(
   (t1.id_store_a = 1
   AND t1.id_store_b = t2.id_store
   AND t3.id = t2.id_store
   AND t2.id_product = 11)
   OR
   (t2.id_product is NULL)
)

例如，如果查看预期输出，id_product的值为空，但您要过滤t2.id_product = 11。因此，null记录永远不会与11匹配，这就是为什么他们被排除在外。

Answer 2

您正在引用WHERE子句左侧的一些列。尝试明确添加OR NULL条件。例如：

SELECT calendar.datefield, t2.*
FROM store_relation t1,store t3, store_product t2
        RIGHT JOIN calendar ON (DATE(t2.created) = calendar.datefield)
        WHERE (calendar.datefield BETWEEN ('2012-07-15') and ('2012-07-20'))
AND ((t1.id_store_a = 1
        AND t1.id_store_b = t2.id_store
        AND t3.id = t2.id_store
        AND t2.id_product = 11)
    OR (t1.id IS NULL AND t2.id IS NULL AND t3.id IS NULL))
ORDER By t2.price

您必须决定要允许哪些表为空。

Answer 3

好的我明白了......谢谢你给我新的想法

SELECT calendar.datefield as DATE, t2.*
FROM store_relation t1,store t3, store_product t2
    RIGHT JOIN calendar ON (DATE(t2.created) = calendar.datefield)
    WHERE (calendar.datefield BETWEEN ('2012-07-15') and ('2012-07-27'))
AND ((t1.id_store_a = 1
    AND t1.id_store_b = t2.id_store
    AND t3.id = t2.id_store
    AND t2.id_product = 11)
OR (t2.id_product IS NULL))
GROUP BY DATE

MYSQL表日历和右键加入

3 个答案: