I have a table that has 2 foreign keys from the same table
UserID Name
1 Alpha
2 Bravo
3 Charlie
4 Delta
5 Foxtrot
Record UserID UserID2
1 1 5
2 3
3 4
Is it possible to display them into multiple rows?
Record Name
1 Alpha
1 Foxtrot
2 Charlie
3 Delta
I tried using INNER JOIN / JOIN but only works with one foreign key (UserID).
More simple way to do this:
Select t2.record AS Record,Name
From t1 inner join t2
on t1.userId = t2.UserID or t1.userId = t2.userid2
You could use two joins, in this case left join to put the values on one row:
select t1.record, t2a.name, t2b.name
from t1 left join
t2 t2a
on t2a.userid = t1.userid left join
t2 t2b
on t2b.userid = t1.userid2;
For separate rows, use union all:
select t1.record, t2.name
from t1 join
t2
on t2.userid = t1.userid
union all
select t1.record, t2.name
from t1 join
t2
on t2.userid = t1.userid2
order by record;
Related
I have 3 tables with names and number of few of my friends.
Table 3 has correct data, table 2 has minute errors in data and table 1 has more than table 2.
if a user exists in table 2 and 3 then show table 3 details in output else table 2 details, if user is not even there in table 2 then show user data from table1.
more like a preference order.
DUMMY DATA:
table 1 :
name phone
abc 2343
bcd 3434
ccd 3455
ffc 4545
table 2 :
name phone
abc 2313
bcd 3414
ccd 3415
table 3 :
name phone
abc 2344
bcd 3431
expected output :
name phone
abc 2344
bcd 3431
ccd 3415
ffc 4545
I tried this query but unable to find correct output.
select phone,
coalesce(table1.name, TABLE2.name,TABLE3.name) as namee
FROM TABLE1
left JOIN TABLE2
ON table1.name = table2.name
INNER JOIN table3
ON table3.name = table2.name
Would be a huge, huge heeelppppp.
Gordon was close; he had the preference backwards. Please make sure you understand why the script works.
-- grab all our preferred data first
select t3.*
from table3 t3
union all
-- grab anything that doesn't exist in our preferred table
select t2.*
from table2 t2
where not exists (select 1 from table3 t3 where t3.name = t2.name)
union all
-- grab anything that doesn't exist in our preferred tables
select t1.*
from table1 t1
where not exists (select 1 from table2 t2 where t2.name = t1.name) and
not exists (select 1 from table3 t3 where t3.name = t1.name);
Use union all:
select t1.*
from table1 t1
union all
select t2.*
from table2 t2
where not exists (select 1 from table1 t1 where t1.name = t2.name)
union all
select t3.*
from table3 t3
where not exists (select 1 from table1 t1 where t1.name = t3.name) and
not exists (select 1 from table2 t2 where t2.name = t3.name);
I have the following tables where a few of the columns are included here:
Table 1:
Id RefId PhoneNumber
1 11 919191
2 11 888888
3 11 919191
Table 2:
Id RefId City UniqueId
1 11 Mumbai 111
2 11 Pune 222
3 11 Nashik 333
I want a few columns from Table1 and Table2. Common in both table is RefId. Table2 has UniqueId which is primary key of Table2. If I do an inner join based on RefId I will get 9 records, but I want 3. How do I get that?
Here is my query:
SELECT T1.PhoneNumber,T2.City,T2.UniqueId,T2.RefId
FROM Table1 T1
INNER JOIN Table2 T2
ON T1.RefId = T2.RefId
If the ID is used to join as well then
SELECT t1.Id, t1.RefId, t1.PhoneNumber, t2.City, t2.UniqueId
FROM Table1 t1
INNER JOIN Table2 t2
ON t1.Id = t2.Id
AND t1.RefId = t2.RefId
If the Ids are randomly generated them you probably shouldn't join on them.
If the Ids were random but all of the PhoneNumbers were for the same place then you could just pick the Minimum value PhoneNumber (or Max)
SELECT t2.RefId, t1.PhoneNumber, t2.City, t2.UniqueId
FROM Table2 t2
INNER JOIN (
SELECT RefId, MIN(PhoneNumber) AS PhoneNumber
FROM Table1
GROUP BY RefId
) t1 ON t1.RefId = t2.RefId
how to solve 3 table and group same id?
t1
----------
Id a
1 100
1 600
2 800
t2
----------
Id b
1 600
2 700
3 400
t3
----------
Id c
2 400
3 800
4 100
i want result like this:
Id a b c
------------------------------
1 700 600
2 800 700 400
3 400 800
4 100
Same id group by
do the fact you have id in several table youn should get, eg: using union ,all the id you need for join
select t.id, t1.a, t2.b, t3.c
from (
select id
from t1
union
select id
from t2
union
select id
from t3 ) AS t
left join t1 on t.id = t1.id
left join t2 on t.Id = t2.Id
left join t3 on t.Id = t3.Id
and if you need sum for a,b,c
select t.id, sum(t1.a), sum(t2.b), sum(t3.c)
from (
select id
from t1
union
select id
from t2
union
select id
from t3 ) AS t
left join t1 on t.id = t1.id
left join t2 on t.Id = t2.Id
left join t3 on t.Id = t3.Id
group by t.id
To ensure that you are taking all possible values use full outer join. Though this will not work in mySQL. If that is the case then look at this answer
select coalesce(t1.id,t2.id,t3.id) as id, sum(t1.a) as a, sum(t2.b) as b,sum(t3.c) as c
from t1
outer join t2
on t1.id = t2.id
outer join t3
on t1.id = t3.id
or t2.id = t3.id
group by id
Might be misunderstanding you, but looks like you just need to join the table more than doing a Union Operation on them. Below statement will only return records where all three tables have at least one record with the same id.
SQL would be:
SELECT TBL1.ID,
TBL1.A,
TBL2.B,
TBL3.C
FROM A TBL1 (NOLOCK)
INNER JOIN B TBL2 (NOLOCK) ON TBL1.ID = TBL2.ID
INNER JOIN C TBL3 (NOLOCK) ON TBL1.ID = TBL3.ID
Two questions:
1. Which SQL engine to you use?
2. and do you need to return values where one table does not have the id?
I have two tables:
id
1
2
3
4
t1 AND t2
id | related_id
1 | 2
1 | 3
Where t2 is relationship table between t1 records. What is the best way to get desired output?
t1.id | t1_copy.id
1 | NULL -- want to get this NULL row
1 | 2
1 | 3
Simple JOIN would almost work, however it doesn't give me the first NULL row.
SELECT t1.id, t1_copy.id FROM t1
LEFT JOIN t2 ON t1.id = t2.id
LEFT JOIN t1 t1_copy ON t1_copy.id = t2.related_id
WHERE t1.id = 1
P.S: Yes, I do realize that desired output is wacky.
Seems like a simple UNION should do the trick
SELECT
id,
null as copy_id
FROM
t1
WHERE
exists (select * from t2 where t1.id = t2.id)
UNION ALL
SELECT
t1.id,
t2.related_id
FROM
t1
INNER JOIN t2
ON t1.id = t2.id
SQL Fiddle
SELECT DISTINCT t1.id, t1_copy.id FROM t1
LEFT OUTER JOIN t2 ON t1.id = t2.id
WHERE t1.id = 1
I have the following tables:
T1
ID PRIORITY
1 1
2 1
3 2
4 4
T2
ID SERVICE
1 PSTN
1 ADSL
3 ADSL
T3
ID DEVICE
1 BSC1
3 BSC7
4 BSC7
I want as output
ID PRIORITY SERVICE/DEVICE
1 1 PSTN
1 1 ADSL
1 1 BSC1
2 1
3 2 ADSL
3 2 BSC7
How to bind those tables using UNION ALL? Also I must put WHERE clause for T1 WHERE PRIORITY!=4
Total number in output table for one id should be the summary of T2+T3 (FOR ID=1 2+1=3) but for ID=2 it also SHOULD exist in table output with blank second column.
Thank you
If you are okay using just a UNION and not UNION ALL this should give you what you want
SELECT t1.Id, t1.Priority, COALESCE(t2.Service, '') AS [Service/Device]
FROM t1
LEFT JOIN t2 ON t1.Id = t2.Id
WHERE t1.Priority != 4
UNION
SELECT t1.Id, t1.Priority, COALESCE(t3.Device, '') AS [Service/Device]
FROM t1
LEFT JOIN t3 ON t1.Id = t3.Id
WHERE t1.Priority != 4
SQL Fiddle example
select T1.id , T1.PRIORITY ,T2.SERVICE as service/Device from t1
left outer join T2 on T2.id=T1.id where T1.PRIORITY!=4
union all
select T1.id , T1.PRIORITY ,T3.DEVICE as service/Device from t1
left outer join T3 on T3.id=T1.id where PRIORITY!=4