Question

考虑以下内容：

CREATE TABLE TestPersons
(
PersonID int,
Name varchar(255),
FirstName varchar(255),
Address varchar(255)
)

insert into TestPersons(PersonID, Name, FirstName , Address) Values (1, 'name1', 'firstname1', 'adress1');
insert into TestPersons(PersonID, Name, FirstName , Address) Values (2, 'name2', 'firstname2', 'adress2');
insert into TestPersons(PersonID, Name, FirstName , Address) Values (3, 'name3', 'firstname3', 'adress3');
insert into TestPersons(PersonID, Name, FirstName , Address) Values (4, 'name4', 'firstname4', 'adress4');

首次查询（工作正常）：

SELECT name, firstname, personid, count(name), row_number() over (ORDER BY name, firstname) as rn
FROM testpersons
GROUP BY name, firstname, personid

返回：

name1   firstname1  1   1   1
name2   firstname2  2   1   2
name3   firstname3  3   1   3
name4   firstname4  4   1   4

第二次查询（意外结果）：

SELECT name, firstname, personid, count(name), row_number() over (ORDER BY name desc, firstname desc) as rn
FROM testpersons
GROUP BY name, firstname, personid

返回所有行name4和firstname4：

name4   firstname4  4   1   1
name4   firstname4  3   1   2
name4   firstname4  2   1   3
name4   firstname4  1   1   4

我希望第一个查询的结果更改顺序。

任何想法为什么会这样？

select * from v$version的输出如下：

Oracle Database 12c Release 12.1.0.1.0 - 64bit Production   0
PL/SQL Release 12.1.0.1.0 - Production  0
"CORE   12.1.0.1.0  Production" 0
TNS for 64-bit Windows: Version 12.1.0.1.0 - Production 0
NLSRTL Version 12.1.0.1.0 - Production  0

Answer 1

我不知道你在说什么。下面是我的会话中的直接复制和粘贴，我在发布它们时输入了命令。我从第二个查询中得到了正确的结果。

你有没有告诉我们的事情？您使用的是哪个版本的Oracle？你是如何与它互动的？你的前端是什么？您是直接发送查询还是通过某个应用程序发送查询？

您在下面看到的是Oracle 11.2 XE，SQL * Plus前端。

SQL> CREATE TABLE TestPersons
  2  (
  3  PersonID int,
  4  Name varchar(255),
  5  FirstName varchar(255),
  6  Address varchar(255)
  7  );

Table created.

SQL> insert into TestPersons(PersonID, Name, FirstName , Address) Values (1, 'name1', 'firstname1', 'adress1');
1 row created.
SQL> insert into TestPersons(PersonID, Name, FirstName , Address) Values (2, 'name2', 'firstname2', 'adress2');
1 row created.
SQL> insert into TestPersons(PersonID, Name, FirstName , Address) Values (3, 'name3', 'firstname3', 'adress3');
1 row created.
SQL> insert into TestPersons(PersonID, Name, FirstName , Address) Values (4, 'name4', 'firstname4', 'adress4');
1 row created.

SQL> column name format a10
SQL> column firstname format a18

SQL> SELECT name, firstname, personid, count(name), row_number() over (ORDER BY name, firstname) as rn
  2  FROM testpersons
  3  GROUP BY name, firstname, personid;

NAME       FIRSTNAME            PERSONID COUNT(NAME)         RN
---------- ------------------ ---------- ----------- ----------
name1      firstname1                  1           1          1
name2      firstname2                  2           1          2
name3      firstname3                  3           1          3
name4      firstname4                  4           1          4

4 rows selected.

SQL> SELECT name, firstname, personid, count(name), row_number() over (ORDER BY name desc, firstname desc) as rn
  2  FROM testpersons
  3  GROUP BY name, firstname, personid;

NAME       FIRSTNAME            PERSONID COUNT(NAME)         RN
---------- ------------------ ---------- ----------- ----------
name4      firstname4                  4           1          1
name3      firstname3                  3           1          2
name2      firstname2                  2           1          3
name1      firstname1                  1           1          4

4 rows selected.

Oracle意外的排序行为

1 个答案: