Combining three similar sql queries into a single result - sql

Question

I have a table say (TimeValue) something like this
Time Value Owner
======================
1 10 A
2 20 B
3 30 C
4 40 A
5 50 B
6 60 C
7 70 A
8 80 B
Now I have three sql statement like the followings
select owner, value as 'First sql' from TimeValue where time >= 1 and time <= 3 group by owner
select owner, value as 'Second sql' from TimeValue where time >= 4 and time <= 6 group by owner
select owner, value as 'Third sql' from TimeValue where time >= 7 and time <= 9 group by owner
Now these are the result of the above sql
1.
Value Owner
=================
10 A
20 B
30 C
2.
Value Owner
=================
40 A
50 B
60 C
3
Value Owner
===============
70 A
80 B
90 C
My question, what would be the sql statement if I want the following result??
Owner First SQL Second SQL Third SQL
==================================================
A 10 40 70
B 20 50 80
C 30 60 90
Thank you in advance

Answer 1

One way is to use a CASE statement, like this:
SELECT
owner
, MAX(CASE WHEN time >= 1 AND time <= 3 THEN value ELSE NULL END) AS FIRST
, MAX(CASE WHEN time >= 4 AND time <= 6 THEN value ELSE NULL END) AS SECOND
, MAX(CASE WHEN time >= 7 AND time <= 9 THEN value ELSE NULL END) AS THIRD
FROM TimeValue
GROUP BY owner
Note that you need an aggregating function, such as MAX, around value. In fact, many RDBMS engines would not even take SQL without an aggregating function around it.

Answer 2

SQL FIDDLE
select owner,
SUM(case when (time >= 1 and time <= 3) then value end) as 'FirstSQL',
SUM(case when (time >= 4 and time <= 6) then value end) as 'SecondSQL',
SUM(case when (time >= 7 and time <= 9) then value end) as 'ThirdSQL'
from TimeValue
group by owner
base on your example you should use SUM instead of MAX

Answer 3

The same idea with dasblinkenlight but different approach and I agree on aggregating function, such as MAX or SUM
SELECT
owner,
MAX(IF(time between 1 and 3, value,NULL) ) as first,
MAX(IF(time between 4 and 6, value,NULL) ) as sec,
MAX(IF(time between 7 and 9, value,NULL) ) as third
FROM TimeValue
GROUP BY owner

Answer 4

you can also use self-joins:
select
tv0.owner
, tv0.value sql1
, tv1.value sql2
, tv2.value sql3
from timevalue tv0
inner join timevalue tv1 on tv1.owner = tv0.owner
inner join timevalue tv2 on tv2.owner = tv0.owner
where tv0.time between 1 and 3
and tv1.time between 4 and 6
and tv2.time between 7 and 9