[英]I require to create an SQL or PLSQL Query for merging and ordering data in a table
I am trying to create a SQL query that will help me get a proper ordered output from the below data. 我正在尝试创建一个SQL查询,该查询将帮助我从以下数据中获取适当的有序输出。
Data in table : 表中数据:
Cust num Eff_Date Exp_date
1001 1234 10-01-2010 20-06-2010
1001 1234 20-06-2010 25-06-2010
1001 1234 25-06-2010 12-02-2011
1001 1234 12-02-2011 12-02-2011
1001 3456 12-02-2011 25-07-2012
1001 3456 25-07-2012 25-07-2012
1001 1234 25-07-2012 25-07-2012
1001 1234 25-07-2012 31-12-4700
Expected output of Query : Query的预期输出:
Cust num Eff_Date Exp_date
1001 1234 10-01-2010 12-02-2011
1001 3456 12-02-2011 25-07-2012
1001 1234 25-07-2012 31-12-4700
I would prefer to be able to do the above using a single SQL statement. 我希望能够使用单个SQL语句完成上述操作。 Is it possible to do the above using a single SQL statement?
是否可以使用单个SQL语句完成上述操作? Is there an alternate way to do the above.
是否有其他方法可以执行上述操作。
SELECT
Customer,
`number` AS Number,
MIN(Eff_Date) AS Eff_Date,
MAX(Exp_date) AS Exp_date
FROM tablename
GROUP BY Customer, number
This works for postgres, but it could be adapted to oracle with minor changes, IMHO. 这适用于postgres,但可以进行细微更改以适应Oracle,恕我直言。 Note: I changed the data a bit, because overlapping intervals don't look plausible to me.
注意:我对数据进行了一些更改,因为重叠的间隔对我而言似乎并不合理。
DROP SCHEMA tmp CASCADE;
CREATE SCHEMA tmp ;
SET search_path=tmp;
CREATE TABLE lutser
( cust INTEGER NOT NULL
, num iNTEGER NOT NULL
, eff_date DATE NOT NULL
, exp_date DATE NOT NULL
, PRIMARY KEY (cust, num, eff_date)
);
SET datestyle=german;
INSERT INTO lutser(cust,num,eff_date,exp_date) VALUES
(1001,1234,'10-01-2010', '20-06-2010' )
,(1001,1234,'20-06-2010', '25-06-2010' )
,(1001,1234,'25-06-2010', '12-02-2011' )
,(1001,1234,'12-02-2011', '12-02-2011' )
,(1001,3456,'12-02-2011', '25-07-2012' )
,(1001,3456,'25-07-2012', '25-07-2012' )
,(1001,1234,'25-07-2012', '25-08-2012' ) -- added a month to get unique PK
,(1001,1234,'25-08-2012', '31-12-4700' ) -- and here as well
;
VACUUM ANALYZE lutser;
-- SELECT * FROM lutser ORDER BY cust,num,eff_date;
-- EXPLAIN ANALYZE
WITH RECURSIVE island AS
( SELECT cust,num,eff_date,exp_date
FROM lutser l0
WHERE NOT EXISTS
( SELECT *
FROM lutser nx
WHERE nx.cust = l0.cust AND nx.num = l0.num
AND nx.eff_date < l0.eff_date
AND nx.exp_date >= l0.eff_date
)
UNION -- ALL
SELECT isl.cust,isl.num, isl.eff_date,l1.exp_date
FROM lutser l1
JOIN island isl ON isl.cust = l1.cust AND isl.num = l1.num
AND isl.eff_date < l1.eff_date
AND isl.exp_date >= l1.eff_date
)
SELECT DISTINCT ON (cust,num,eff_date) *
FROM island
ORDER BY cust,num,eff_date
;
Result: 结果:
NOTICE: drop cascades to table tmp.lutser
DROP SCHEMA
CREATE SCHEMA
SET
NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "lutser_pkey" for table "lutser"
CREATE TABLE
SET
INSERT 0 8
VACUUM
cust | num | eff_date | exp_date
------+------+------------+------------
1001 | 1234 | 10.01.2010 | 20.06.2010
1001 | 1234 | 25.07.2012 | 25.08.2012
1001 | 3456 | 12.02.2011 | 25.07.2012
(3 rows)
in Oracle, we can use analytic functions to group islands together: 在Oracle中,我们可以使用分析功能将孤岛分组在一起:
SQL> select c.cust, c.num, min(eff_date) eff_date, max(exp_Date) exp_date
2 from (select c.cust, c.num, c.eff_date, c.exp_date, max(rn) over (partition by cust, num order by eff_date) grp
3 from (select c.cust, c.num, c.eff_date, c.exp_date,
4 case
5 when lag(exp_date, 1) over (partition by cust, num order by eff_date) != eff_date
6 then
7 row_number() over (partition by cust, num order by eff_date)
8 when row_number() over (partition by cust, num order by eff_date) = 1
9 then
10 1
11 end rn
12 from cust c) c) c
13 group by c.cust, c.num, grp
14 order by eff_date;
CUST NUM EFF_DATE EXP_DATE
---------- ---------- ---------- ----------
1001 1234 10-01-2010 12-02-2011
1001 3456 12-02-2011 25-07-2012
1001 1234 25-07-2012 31-12-4700
SQL>
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.