SQL - 创建一个连接的临时表

Question

我希望将两个表连接到一个临时表中，然后在选择查询中使用临时表。这是我要创建的临时表的选择语句:

select program, event
from OMEGA.HP
inner join POM.GT
on program = substring(name,7,4)
where LENGTH(name)= 25

为上述创建临时表的最简单方法是什么？

Answer 1

您可以创建一个临时表(并且您可能想要)，但如果您还不知道，我想指出您可以在这样的查询中创建一个虚拟临时表

SELECT * 
FROM (
  select program, event
  from OMEGA.HP
  inner join POM.GT on program = substring(name,7,4)
  where LENGTH(name)= 25
) AS Virtual_table

你甚至可以像这样加入另一个这样的表:

SELECT * 
FROM (
  select program, event
  from OMEGA.HP
  inner join POM.GT on program = substring(name,7,4)
  where LENGTH(name)= 25
) AS v_table74
join (
  select program, event
  from OMEGA.HP
  inner join POM.GT on program = substring(name,2,5)
  where LENGTH(name)= 25
) as v_table25 on v_table74.program = v_table25.program