Table1 (ID, Col1, col2, col3, col4)
Table2 (ID, Col5, col6)
-----------------SP-------------------
set #Ids = '1,2,3,4,5,6,7,8,9' // Input paremeter (can be NULL)
Create Table #Tabel2
(
Id int
)
Insert into #table2 select * from dbo.Split(#Ids, ',')
NOW #table2 has: 1 2 3 4 5 6 7 8 9
Scenario
Select t1.Col1,t1.col2,t1.col3
FROM Table1 as t1
INNER JOIN Table2 as t2 ON t1.Col1=t2.Col2
AND (#Ids is null OR t1.ID in (Select Id from #Table2))
Question
How to replace IN with conditional inner join?
Because you used alias t which was never defined in your query, it is not clear to me which table ID should be joined on. I took a guess and used t1.
Select t1.Col1,t1.col2,t1.col3
FROM Table1 as t1
INNER JOIN Table2 as t2 ON t1.Col1=t2.Col2
left outer join #Table2 ids on #Ids is null or t1.ID = ids.ID --maybe this should be t2.ID = ids.ID?
Unless I'm misunderstanding (it is friday afternoon after all) you want all rows from Table1/Table2, matched to #Table2 where possible, but everything if #Table2 is empty - this is simply an outer join.
SELECT t.Col1,
t.col2,
t.col3
FROM Table1 AS t1
INNER JOIN Table2 AS t2
ON t1.Col1 = t2.Col2
LEFT OUTER JOIN #Table2 t3
ON t2.ID = t3.ID
In SQL Server 2008, you can use CASE statements in your join clause, for example:
SELECT *
FROM table1
INNER JOIN table2 ON CASE WHEN table1.column1 = 'this' THEN null ELSE 'that' END = table2.column1
Related
How can I do something like select * from T1 inner join T2 on (T1.ID=T2.ID OR T1.ID2=T2.ID)
When I execute this code, it seems to fall in a infinity loop so I guess I'm wrong.
In other words, how can I match one of two columns from T1 to one column from T2
T1
ID ID2
1 10
2 20
T2
ID value
1 dummy10
20 dummy20
Result
ID ID2 value
1 10 dummy10
2 20 dummy20
Try to do like this:
select *
from T1, T2
where T1.ID = T2.ID or T1.ID2 = T2.ID
you can use 2 select statements with union, like this:
select
t1.ID,
t1.ID2,
t2.value
from Table1 as t1
inner join Table2 as t2 on t1.ID = t2.ID
UNION
select
t1.ID,
t1.ID2,
t2.value
from Table1 as t1
inner join Table2 as t2 on t1.ID2 = t2.ID
/* this will exclude values selected by other statement */
where t1.ID2 not in (select ID2 from Table1 inner join Table2 on Table1.ID = Table2.ID)
The only issue I can see with the code you provide is that you have not specified from which table you want the common column ID to be selected:
proc sql;
select
t1.*
,t2.value
from t1
inner join t2
on t1.id = t2.id or t1.id2 = t2.id;
quit;
Otherwise, your code should work. Perhaps the size of the data being joined is the problem?
select t.* from table1 t where t.id NOT IN(
select Id from t2 where usrId in
(select usrId from t3 where sId=value));
I the result i need is like if there are matching id's in t1 and t2 then those id's should be omitted and only the remaining rows should be given to me. I tried converting into join but it is giving me the result i wanted. Below is my join query.
SELECT t.* FROM table1 t JOIN table2 t2 ON t.Id <> t2.Id
JOIN table3 t3 ON t3.Id=t2.Id WHERE t3.sId= :value
This doesn't feth me the correct result. it was returning all the rows, but i want to restrict the result based on the matching id's in table t1 and table t2. Matching id's should be ommited from the result.I will be passing the value for sId.
I believe this to be an accurate refactor of your query using joins. I don't know if we can do away with the subquery, but in any case the logic appears to be the same.
select t1.*
from table1 t1
left join
(
select t2.Id
from table2 t2
inner join table3 t3
on t2.usrId = t3.usrId
where t3.sId = <value>
) t2
on t1.Id = t2.Id
where t2.Id is null
Let's break down and solve problem step by step.
So your query
select t.* from table1 t where t.id NOT IN(
select Id from t2 where usrId in
(select usrId from t3 where sId=value));
on converting the inner query to JOIN will yield
select t.* from table1 t where t.id NOT IN
(SELECT T2.ID FROM T2 JOIN T3 on T2.UsrID =T3.UsrID and T3.sID=value)
which on further converting to JOIN with outer table will be
select t.* from table1 t LEFT JOIN
(SELECT T2.ID FROM T2 JOIN T3 on T2.UsrID =T3.UsrID and T3.sID=value)t4
ON t.id =T4.ID
WHERE t4.ID is NULL
In case you completely want to remove sub-query you can try like this
SELECT t.*
FROM table1 t
LEFT JOIN T2
ON T.ID=T2.ID
LEFT JOIN T3
ON T3.UsrId=T2.UsrID AND T3.sId=value
WHERE T3.UsrID IS NULL
select *
from table1 t1,
table2 t2,
table3 t3
where t2.parent_id = t1.row_id
and t2.xyz is not null
and (
select count(*)
from table3
where xyz = t2.row_id
) = 0;
Will it work?
I am using the alias t2 within my subquery.
My requirement is to check is to specify condition in where clause such that there is no record present in table3 where column xyz of table3 is stored as row_id of table2.
You can use NOT EXISTS to assert that there is no row returned from the subquery. Use modern explicit join syntax instead of comma based legacy syntax. No need to join table3 outside (you were making a cross join effectively).
select *
from table1 t1
join table2 t2 on t2.parent_id = t1.row_id
where t2.xyz is not null
and not exists (
select 1
from table3
where xyz = t2.row_id
);
I have some set of records, but now i have to select only those records from this set which have theeir Id in either of the two tables.
Suppose I have table1 which contains
Id Name
----------
1 Name1
2 Name2
Now I need to select only those records from table one
which have either their id in table2 or in table3
I was trying to apply or operator witin inner join like:
select *
from table1
inner join table2 on table2.id = table1.id or
inner join table3 on table3.id = table1.id.
Is it possible? What is the best method to approach this? Actually I am also not able to use
if exist(select 1 from table2 where id=table1.id) then select from table1
Could someone help me to get over this?
Use left join and then check if at least one of the joins has found a relation
select t1.*
from table1 t1
left join table2 t2 on t2.id = t1.id
left join table3 t3 on t3.id = t1.id
where t2.id is not null
or t3.is is not null
I would be inclined to use exists:
select t1.*
from table1 t1
where exists (select 1 from table2 t2 where t2.id = t1.id) or
exists (select 1 from table3 t3 where t3.id = t1.id) ;
The advantage to using exists (or in) over a join involves duplicate rows. If table2 or table3 have multiple rows for a given id, then a version using join will produce multiple rows in the result set.
I think the most efficient way is to use UNION on table2 and table3 and join to it :
SELECT t1.*
FROM table1 t1
INNER JOIN(SELECT id FROM Table2
UNION
SELECT id FROM Table3) s
ON(t.id = s.id)
Alternatively, you can use below SQL as well:
SELECT *
FROM dbo.Table1
WHERE id Table1.IN ( SELECT table2.id
FROM dbo.table2 )
OR Table1.id IN ( SELECT table3.id
FROM Table3 )
I have following query-
select * from
Table1 t1 , table2 t2 ,
(select idCol from table3) t3
My question is - Can I use table t2 inside subquery?
like this
select * from
Table1 t1 , table2 t2 ,
(select idCol, t2.nameCol from table3) t3
Obviously this gives error invalid identifier t2.nameCol
But if I write as follows, it give unnecessaru extra rows
select * from
Table1 t1 , table2 t2 ,
(select idCol, t2.nameCol from table3, table2 t2) t3
any other way to do this?
EDIT
Basically what I am trying to achieve is following
select * from
Table1 t1 , table2 t2 ,
(select
case
when t2.nameCol = 'ABC' then 'ABC'
else idCol
end idCol from table3) t3
To join a table only when certain criteria is met is called an outer join. Here is how:
select *
from table1 t1
inner join table2 t2 on <join criteria here>
left outer join table3 t3 on t2.namecol <> 'ABC' and <join criteria here>;
It may suffice in your case, however, to move the subquery to your SELECT clause:
select
t1.*,
t2.*,
case when t2.namecol = 'ABC' then
'ABC'
else
(select idcol from table3 t3 where <join criteria here>)
end
from table1 t1
inner join table2 t2 on <join criteria here>;
You can try below. I am sure you have some kind of join between t1 and t2. IN such case, you can add same at the end of the statement.
SELECT t1.*,
t2.*,
( SELECT CASE
WHERE t2.nameco1 = 'ABC' THEN 'ABC'
ELSE idcol
END idcol
FROM table3) idcol
FROM table1 t1,
table2 t2