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SQL右联接问题

[英]SQL Right Join issue

My query make a Right Join, but the results is not correct. 我的查询进行了Right Join,但结果不正确。
Null values must be where column NAME_2 is equal with A and I can't figure out what is wrong. Null值必须是NAME_2列与A相等A ,我无法弄清楚哪里出了问题。

Here is the query: 这是查询:

http://sqlfiddle.com/#!6/cd45b/1 http://sqlfiddle.com/#!6/cd45b/1

For the future readers. 对于未来的读者。 The definition of tables: 表的定义:

CREATE TABLE S1 (TIME_1 DateTIME, INTERVAL_1 INT, NAME_1 varchar(20),INITIAL_VAL int);
CREATE TABLE S2 (TIME_2 DateTIME, INTERVAL_2 INT, NAME_2 varchar(20), FINAL_VAL int);

The data inserts related to the question: 与问题有关的数据插入:

INSERT INTO S1 values('10.02.2017 00:00',1, 'B',13);
INSERT INTO S1 values('10.02.2017 01:00',2, 'B',14);
INSERT INTO S1 values('10.02.2017 02:00',3, 'B',10);
INSERT INTO S1 values('10.02.2017 03:00',4, 'B',15);

INSERT INTO S1 values('10.02.2017 00:00',1, 'C',42);
INSERT INTO S1 values('10.02.2017 01:00',2, 'C',10);
INSERT INTO S1 values('10.02.2017 02:00',3, 'C',22);
INSERT INTO S1 values('10.02.2017 03:00',4, 'C',18);


INSERT INTO S2 values('10.02.2017 00:00',1, 'A',12);
INSERT INTO S2 values('10.02.2017 01:00',2, 'A',13);
INSERT INTO S2 values('10.02.2017 02:00',3, 'A',9);
INSERT INTO S2 values('10.02.2017 03:00',4, 'A',16);

INSERT INTO S2 values('10.02.2017 00:00',1, 'B',16);
INSERT INTO S2 values('10.02.2017 01:00',2, 'B',22);
INSERT INTO S2 values('10.02.2017 02:00',3, 'B',20);
INSERT INTO S2 values('10.02.2017 03:00',4, 'B',10);

INSERT INTO S2 values('10.02.2017 00:00',1, 'C',42);
INSERT INTO S2 values('10.02.2017 01:00',2, 'C',15);
INSERT INTO S2 values('10.02.2017 02:00',3, 'C',22);
INSERT INTO S2 values('10.02.2017 03:00',4, 'C',19); 

Initial query from the question: 来自问题的初始查询:

WITH CTE1
AS
(
    SELECT ROW_NUMBER() OVER (ORDER BY NAME_1) AS V1, * FROM S1
)
,CTE2
AS
(
    SELECT ROW_NUMBER() OVER (ORDER BY NAME_2) AS V2,* FROM S2
)
SELECT
CTE2.NAME_2,
CTE2.TIME_2,
INTERVAL_2,
CTE1.INITIAL_VAL,
CTE2.FINAL_VAL
FROM CTE1
RIGHT JOIN CTE2
ON CTE1.V1=CTE2.V2

Your right join is matching over ROW_NUMBER produced. 您的右侧ROW_NUMBER产生的ROW_NUMBER匹配。 So it doesn't matter that it's NAME_2 value: A , doesn't have a match with NAME_1 value. 因此,它的NAME_2值无关紧要: A ,与NAME_1的值不匹配。

It is matching A from table S1 with B from table S2 , because they both get the same ROW_NUMBER 它匹配A从表S1B从表S2 ,因为他们都得到同样的ROW_NUMBER

Please run this to see what is matched when you do right join: 请运行此命令以查看正确加入后的匹配项:

SELECT ROW_NUMBER() OVER (ORDER BY NAME_1) AS V1, * FROM S1;
SELECT ROW_NUMBER() OVER (ORDER BY NAME_2) AS V2,* FROM S2;

Edit: Answering to your question from the comment. 编辑:从评论中回答您的问题。 It is very hard to know what exactly do you need to build, but I think that the interval might bring some interesting results: 很难知道您到底需要构建什么,但是我认为间隔可能会带来一些有趣的结果:

WITH CTE1
AS
(
    SELECT ROW_NUMBER() OVER (ORDER BY NAME_1) AS V1, * FROM S1
)
,CTE2
AS
(
    SELECT ROW_NUMBER() OVER (ORDER BY NAME_2) AS V2,* FROM S2
)
SELECT
CTE2.NAME_2,
CTE2.TIME_2,
INTERVAL_2,
CTE1.INITIAL_VAL,
CTE2.FINAL_VAL
FROM CTE1
RIGHT JOIN CTE2
ON CTE1.NAME_1=CTE2.NAME_2 AND CTE1.INTERVAL_1 = CTE2.INTERVAL_2

Is the interval always Same for Name_1 and Name_2?. 名称_1和名称_2的间隔是否始终相同? Otherwise it will go wrong again. 否则它将再次出错。 Not sure whether you need a join only on Name column or combination of Name & interval. 不确定只需要在“名称”列上联接还是“名称和间隔”组合。 Please ignore if answer given by Jakub Szumiato is already working for you. 如果Jakub Szumiato给出的答案已经为您服务,请忽略。 I have taken a simple test data and executed with the Query given by Jakub Szumiato. 我已经获取了一个简单的测试数据,并使用Jakub Szumiato给出的Query执行。 This is the output. 这是输出。

在此处输入图片说明

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