Welcome to ShenZhenJia Knowledge Sharing Community for programmer and developer-Open, Learning and Share
menu search
person
Welcome To Ask or Share your Answers For Others

Categories

I have a query:

SELECT s.period, s.year, s.amount 
FROM salaries s

I would like to select from salaries table only the rows that have period and year equal to:

SELECT p.period, p.years 
FROM periods p

I know that the simplest way would be use join, but the problem is - that in the application I can add only a clause after WHERE

So the solution should be:

SELECT s.period, s.year, s.amount 
FROM salaries s 
WHERE ...

Is that possible?

EDIT: The result should be the same as:

SELECT s.period, s.year, s.amount 
FROM salaries s
  JOIN periods p ON s.period = p.period AND s.year = p.year
See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
thumb_up_alt 0 like thumb_down_alt 0 dislike
636 views
Welcome To Ask or Share your Answers For Others

1 Answer

You can use more than one column for an IN condition:

SELECT s.period, s.year, s.amount 
FROM salaries s
where (s.year, s.period) in (select year, period from periods)

But Gordon's not exists solution is probably faster.


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
thumb_up_alt 0 like thumb_down_alt 0 dislike
Welcome to ShenZhenJia Knowledge Sharing Community for programmer and developer-Open, Learning and Share
...