基于第一行的 Oracle Cross Join

Question

我正在使用 Oracle 数据库捕获交易数据。

Table 1：用户打开调查表的交易数据。拥有电子邮件地址的收件人可能会多次打开调查表，但没有填写并提交。同样的调查可以通过Survey_No.

来确定

INSERT INTO survey_open (SURVEY_NO,EMAIL,DATE) VALUES (1, john@email.com,5/21/2020);
INSERT INTO survey_open (SURVEY_NO,EMAIL,DATE) VALUES (1, john@email.com,5/19/2020);
INSERT INTO survey_open (SURVEY_NO,EMAIL,DATE) VALUES (1, john@email.com,5/10/2020);
INSERT INTO survey_open (SURVEY_NO,EMAIL,DATE) VALUES (1, john@email.com,5/3/2020);
INSERT INTO survey_open (SURVEY_NO,EMAIL,DATE) VALUES (1, john@email.com,5/1/2020);
INSERT INTO survey_open (SURVEY_NO,EMAIL,DATE) VALUES (2, john@email.com,3/1/2020);
INSERT INTO survey_open (SURVEY_NO,EMAIL,DATE) VALUES (2, john@email.com,3/3/2020);
INSERT INTO survey_open (SURVEY_NO,EMAIL,DATE) VALUES (3, john@email.com,2/1/2020);

Table 2：提交调查的用户交易数据。他们可以一次又一次地重新提交他们的选择。同样，survey_no 将提供有关响应所针对的调查的信息。

INSERT INTO survey_fill (SURVEY_NO,EMAIL,DATE) VALUES (1, john@email.com,5/21/2020);
INSERT INTO survey_fill (SURVEY_NO,EMAIL,DATE) VALUES (1, john@email.com,5/15/2020);
INSERT INTO survey_fill (SURVEY_NO,EMAIL,DATE) VALUES (1, john@email.com,5/15/2020);
INSERT INTO survey_fill (SURVEY_NO,EMAIL,DATE) VALUES (1, john@email.com,5/15/2020);
INSERT INTO survey_fill (SURVEY_NO,EMAIL,DATE) VALUES (2, john@email.com,3/15/2020);
INSERT INTO survey_fill (SURVEY_NO,EMAIL,DATE) VALUES (2, john@email.com,3/15/2020);
INSERT INTO survey_fill (SURVEY_NO,EMAIL,DATE) VALUES (2, john@email.com,3/15/2020);
INSERT INTO survey_fill (SURVEY_NO,EMAIL,DATE) VALUES (3, john@email.com,3/1/2020);

我试图获得的预期输出是形成一个 table，它根据作为加入代理有意义的最近日期加入上述两个 table。 survey_open table 上的哪笔交易被标记为 filled_date 并不那么重要。由于 survey_id 和电子邮件是多对多的，我不想形成交叉连接。

Answer 1

尝试对两个表中的项目进行编号

with o as(
  select so.*, row_number() over(partition by survey_no order by open_date) rn
  from survey_open so
), f as (
  select sf.*, row_number() over(partition by survey_no order by fill_date) rn
  from survey_fill sf
)
select o.survey_no
     , o.email
     , o.open_date
     , (select min(f.fill_date) 
         from f 
         where f.survey_no = o.survey_no 
           and f.fill_date >= o.open_date
           and f.rn >= o.rn) as fill_date
  from o 
order by o.survey_no, o.rn desc

基于第一行的 Oracle Cross Join

Oracle Cross Join based on first row

sql

oracle

join

cross-join