Okay, I am trying to write a query from a poor table structure.
Below is something that I want to achieve:
Table 1: List of Items
T1C1 T1C2
A Fred
B Bart
C Carl
Table 2: Second list of Items
T2C1 T2C2
1 Chocolate
2 Cake
3 Pie
4 Fish
5 Pizza
Table 3: Joining table
T3C1 T3C2 T3C3
1 A Y
4 A Y
5 A N
1 B N
2 B Y
5 B Y
1 C Y
2 C N
3 C Y
Result
Select query based on a person in Table 1.
However if the value is not in Table 3 then R1C4 should default to N
R1C1 R1C2 R1C3 R1C4
1 Chocolate A Y
2 Cake A N
3 Pie A N
4 Fish A Y
5 Pizza A N
I've assumed a few details to come up with the following:
DECLARE #UserId CHAR
SET #UserId = 'A'
SELECT T2.T2C1 AS R1C1,
T2.T2C2 AS R1C2,
COALESCE(T3.T3C2, #UserId) AS R1C3,
COALESCE(T3.T3C3, 'N') AS R1C4
FROM Table2 AS T2
LEFT JOIN Table3 AS T3 ON T3.T3C1 = T2.T2C1 AND T3.T3C2 = #UserId
Assumption: example output is for user Fred.
To ensure that we see all entries from Table2 we use a LEFT JOIN on the link table (Table3).
We have to COALESCE the values for the two records that don't exist in the link table.
Note that this only works if we filter to one user, as per the expected output.
View my SQL Fiddle for full example.
declare #filter varchar(1)
select #filter= T1C1 from Table_1 where T1C2='Fred';
with CteResult (R1C1,R1C2,R1C3,R1C4)as
(select T2C1 as R1C1,T2C2 as R1C2,T3C2 as R1C3, T3C3 as R1C4 from table_2 A
inner join Table_3 B on T2C1 =T3C1
where T3C2=#filter)
select T2C1 as R1C1,T2C2 as R1C2,coalesce(R1C3,#filter) as R1C3,
case when R1C4 is null then 'N' else R1C4 end R1C4
from table_2 A left outer join CteResult B
on B.R1C1=A.T2C1
Related
I have the table 'Table01' which contains the keys that should be mandatory:
id
1
2
3
4
And I also have the table 'Table02' which contains the records to be filtered:
id
customer
weight
1
a
100
2
a
300
3
a
200
4
a
45
1
b
20
2
b
100
3
b
17
1
c
80
4
c
90
2
d
30
3
d
30
4
d
50
So I want to identify which are the mandatory id's that the table 'Table02' does not have, and in turn identify which is the 'customer' of each id's that the table 'Table02' does not have.
The resulting table should look like this:
customer
id
b
4
c
2
c
3
d
1
What I have tried so far is a 'rigth join'.
proc sql;
create table table03 as
select
b.id
from table02 a
right join table01 b
on a.id=b.id
where a.id is null;
run;
But that query is not identifying all the id's that should be mandatory.
I hope someone can help me, thank you very much.
here is one way:
select cl.customerid , a.id
from
Table1 a
cross join
( select customerid
from table2
group by customerid
) cl
where not exists ( select 1 from table2 b
where b.customerid = cl.customerid
and b.id = a.id
)
You can use an EXCEPT between two sub-selects. The first creates a matrix of all possibilities, and the except table is a selection of the extant customers.
Example:
data ids;
do id = 1 to 4; output; end;
run;
data have;
input id customer $ weight;
datalines;
1 a 100
2 a 300
3 a 200
4 a 45
1 b 20
2 b 100
3 b 17
1 c 80
4 c 90
2 d 30
3 d 30
4 d 50
run;
proc sql;
create table want(label='Customers missing some ids') as
select matrix.*
from
(select distinct have.customer, ids.id from have, ids) as matrix
except
(select customer, id from have)
;
quit;
If you are doing it in SQL server. Something like #eshirvana above posted, but also you can use with cte:
;with cte as
(
SELECT t1.id, t2.Customer
FROM Table01 t1
cross join (select distinct customer from Table02)
)
SELECT a.customer, a.id FROM cte a
LEFT JOIN Table02 b
ON a.id=b.id AND a.customer=b.customer
where b.id is null
I have these 3 tables
Table 1:
id_Table1 field_table1_1 field_table1_2
1 A B
2 C D
3 E F
Table 1:
id_Table2 field_table2_1 field_table2_2
4 G H
5 I J
List item
Table 3:
id_Table3 id_Table1 id_Table2
1 1 4
2 1 5
3 2 5
So table 3 holds the relation between table 1 and 2.
What I want to do, is with a query, get all the fields in the table 1, plus one extra field that contains all the ids of the table 2 separated by coma.
So the result should be something like this:
id_Table1 field_table1_1 field_table1_2 id_Table2
1 A B 4, 5
2 C D 5
3 E F
One option use a lateral join and string_agg():
select t1.*, x.*
from table1 t1
outer apply (
select string_agg(t3.id_table2) id_table2
from table3 t3
where t3.id_table1 = t1.id_table1
) x
There is no need to bring table2 to get the results you want.
I have a three tables
Table 1
Id Department
1 A
2 B
3 C
4 D
Table 2
Id DepartId Name
1 1 ABC
2 1 DEF
3 1 ASD
4 2 FGH
5 2 HJK
6 3 ZXC
Table 3
Id Depart Area
1 A pp
2 B
3 C nn
4 D oo
I need the result
Id Depart Name Area
1 A ABC pp
2 B FGH Null
3 C ZXC nn
4 D NULL oo
I need one matching entry from table 2 and table 3 to corresponding entry in the table 1
Do a left join to also get t1 rows without any reference in the t2 table. GROUP BY to get only 1 row per Department.
select t1.id, t1.Department, min(t2.Name)
from t1
left join t2 on t1.id = t2.DepartId
group by t1.id, t1.Department
I think I would do this with a correlated subquery:
select t1.*,
(select t2.name
from t2
where t1.id = t2.DepartId and rownum = 1
) as t2name
from t1;
This saves the overhead of an aggregation. An index on t2(DepartId, name) is optimal for this query.
by the way not the answer to your specific question but if instead of just one you want all the names you can use listagg
SELECT t1.id,
department,
LISTAGG (name, ',') WITHIN GROUP (ORDER BY name) names
FROM t1, t2
WHERE t1.id = t2.departId(+)
GROUP BY t1.id, department
ORDER BY 1
ID Department Names
1 A ABC,ASD,DEF
2 B FGH, HJK
3 C ZXC
4 D
I try to get select from two tables and put some data from one to other with ussing WHERE
(PL/SQL)
I have two tables like those:
table1
ID NAME COLOR COMPANY_SHORT_NR
1 a Green 1
2 b Red 23
3 c Blue null
4 a Green null
5 g Green 1
table2
ID SHORT COMP_NAME
1 1 company_name_1
2 23 comapny_name_2
and now I would like to get all data from table 1 with companies names and if its null get info it is null like that
1 a Green company_name_1
2 b Red comapny_name_2
3 c Blue null
4 a Green null
5 g Green company_name_1
I tried do it like this:
select ID
,NAME
,COLOR
,COMPANY_SHORT_NR
from table1
,table2
where COMPANY_SHORT_NR = SHORT
but this give me only not null values:
1 a Green company_name_1
2 b Red comapny_name_2
5 g Green company_name_1
if i use sth like this:
select ID
,NAME
,COLOR
,COMPANY_SHORT_NR
from table1
,table2
where COMPANY_SHORT_NR = SHORT or COMPANY_SHORT_NR is null
I get thousends of records ...
If I use only IS NULL than it returns me only 2 rows as it should be.
Where I make mistake ?
You have to use left join as below
select ID
,NAME
,COLOR
,COMPANY_SHORT_NR
from table1 t1
left join table2 T2 on t1.COMPANY_SHORT_NR = t2.SHORT
you neen OUTER JOIN for that
select ID
,NAME
,COLOR
,COMPANY_SHORT_NR
from table1
LEFT OUTER JOIN table2 ON ( COMPANY_SHORT_NR = SHORT )
wouldn't it be better to join the tables? like SELECT ID, NAME, COLOR, COMPANY_SHORT_NR FROM table1 t1 LEFT JOIN table2 t2 on t2.SHORT = t1.COMPANY_SHORT_NR WHERE 1
I have the following tables in a Hive database:
table1:
id t X
1 1 a
1 4 a
2 5 a
3 10 a
table2:
id t Y
1 3 b
2 6 b
2 8 b
3 15 b
And I would like to merge them to have a table like:
id t Z
1 1 a
1 3 b
1 4 a
2 5 a
2 6 b
2 8 b
3 10 a
3 15 b
Basically what I want to do is :
a join on the column id (that part is easy)
merge the columns table1.t and table2.t into a new column t
have the variable Z that is equal to table1.X if the corresponding t comes from table1.t, and table2.Y if it comes from table2.t
order the table by id and then by t (that shouldn't be too hard)
I have no idea on how to do the parts 2 and 3. I tried with an outer join on
table1.id = table2.id and table1.t = table2.t, but it doesn't merge the two columns t.
Any pointer would be appreciated. Thanks!
CREATE TABLE table3 as SELECT * FROM (SELECT id,t,X as Z FROM t3_1 UNION ALL SELECT id,t,Y as Z FROM t3_2) u1 order by id,t;
Although not always required, using a subquery for the union'd queries help to organize, plus you can then reference the fields from the union (e.g. u1.id ) in other parts of the query.
You'll need the alias on the 3rd column to make the schemas match. If the source table name was not already a column, you could do something like this:
select * from (select id,t,'a' from t3_1 UNION ALL select id,t,'b' from t3_2) u1;
Try this one. It will insert in table 3, all the values from the other 2 tables
INSERT INTO table3 ( t, Z )
SELECT t, X
FROM table1
UNION ALL
SELECT t, Y
FROM table2