在 ORACLE 中查找所有可能的组合列值 SQL

Question

你能帮我解决下面的问题吗：

我有以下 table 个数据。

EmpNo	Name	City
1	John	US
2	Miranda	US
3	Pete	US
4	Jack	US
5	Kathy	UK
6	Tanni	UK
7	Sally	UAE

我想要如下输出：

City	Name1	Name2
US	John	Miranda
US	John	Pete
US	John	Jack
US	Miranda	Pete
US	Miranda	Jack
US	Pete	Jack
UK	Kathy	Tanni

PLSQL 我们可以写块来得到这个输出。但是是否可以单独使用 SQL 代码获得输出？

Answer 1

看起来像是自连接。

SQL> with temp (empno, name, city) as
  2    (select 1, 'John'   , 'US'  from dual union all
  3     select 2, 'Miranda', 'US'  from dual union all
  4     select 3, 'Pete'   , 'US'  from dual union all
  5     select 4, 'Jack'   , 'US'  from dual union all
  6     select 5, 'Kathy'  , 'UK'  from dual union all
  7     select 6, 'Tanni'  , 'UK'  from dual union all
  8     select 7, 'Sally'  , 'UAE' from dual
  9    )
 10  select a.city, a.name, b.name
 11  from temp a join temp b on a.city = b.city and a.name < b.name
 12  order by a.city, a.name;

CIT NAME    NAME
--- ------- -------
UK  Kathy   Tanni
US  Jack    Miranda
US  Jack    John
US  Jack    Pete
US  John    Pete
US  John    Miranda
US  Miranda Pete

7 rows selected.

SQL>

Answer 2

with
  input_table (empno, name, city) as (
    select 1, 'John'   , 'US'  from dual union all
    select 2, 'Miranda', 'US'  from dual union all
    select 3, 'Pete'   , 'US'  from dual union all
    select 4, 'Jack'   , 'US'  from dual union all
    select 5, 'Kathy'  , 'UK'  from dual union all
    select 6, 'Tanni'  , 'UK'  from dual union all
    select 7, 'Sally'  , 'UAE' from dual
  )
-- end of sample data (for testing only, not part of the query)
-- remove WITH clause and use your actual table name below
select t1.city, t1.name as name1, t2.name as name2
from   input_table t1 inner join input_table t2
                      on t1.city = t2.city and t1.empno < t2.empno
order  by t1.empno, t2.empno   -- if needed
;

CITY  NAME1    NAME2  
----- -------- --------
US    John     Miranda
US    John     Pete   
US    John     Jack   
US    Miranda  Pete   
US    Miranda  Jack   
US    Pete     Jack   
UK    Kathy    Tanni

在 ORACLE 中查找所有可能的组合列值 SQL

Find all possible combinations column value in ORACLE SQL

sql

oracle

plsql