If I have two columns:
col1 col2 amount
1 2 15
2 3 12
1 3 10
3 1 4
3 2 3
And I perform a group by col1,col2 then I get a row for each combination (present) in the data.
My problem though is, that I dont always have all combinations, but I would want to return a row of each combination still. So if there isn't a combination. for example 2 -> 1 then I would want its value to be 0.
Can I somehow specify the "levels" of the group by?
I'm using SQL Oracle.
and the outcome I would want is:
1 -> 2 15
1 -> 3 10
2 -> 1 0
2 -> 3 12
3 -> 1 4
3 -> 2 3
With their respective amount, and 0 if they dont exist, or null works. ( I have a filter to exclude where col1 and col2 are same)
Generate all the rows using cross join and then filter for the ones you want:
select c1.col1, c2.col2, coalesce(t.amount, 0)
from (select 1 as co1l from dual union all
select 2 as co1l from dual union all
select 3 as co1l from dual
) c1 cross join
(select 1 as co12 from dual union all
select 2 as co12 from dual union all
select 3 as co12 from dual
) c2 left join
t
on t.col1 = c1.col1 and t.col2 = c2.col2
where c1.col1 <> c2.col2;
Related
Recently, I am trying to create a table. I have a column that contains 'a', 'b', 'c' and would like to cross join it with 1,2,3 in to the table below.
However, I don't have a table that contains values 1,2,3 and need to do it without creating a table.
Can I achieve this without creating any table? Thanks a lot!
Col1
a
b
c
Col1 Col2
a 1
b 1
c 1
a 2
b 2
c 2
a 3
b 3
c 3
Use a CTE instead:
SQL> with
2 a (col) as
3 (select 'a' from dual union all
4 select 'b' from dual union all
5 select 'c' from dual
6 ),
7 b (col) as
8 (select 1 from dual union all
9 select 2 from dual union all
10 select 3 from dual
11 )
12 select a.col, b.col
13 from a cross join b;
C COL
- ----------
a 1
a 2
a 3
b 1
b 2
b 3
c 1
c 2
c 3
9 rows selected.
SQL>
You can use:
SELECT *
FROM table1
CROSS JOIN (SELECT LEVEL AS col2 FROM DUAL CONNECT BY LEVEL <= 3);
or
WITH data (col1, col2) AS (
SELECT col1, 1 FROM table1
UNION ALL
SELECT col1, col2 + 1 FROM data WHERE col2 < 3
)
SELECT * FROM data;
Which, given your sample data:
CREATE TABLE table1 (col1) AS
SELECT 'a' FROM DUAL UNION ALL
SELECT 'b' FROM DUAL UNION ALL
SELECT 'c' FROM DUAL;
Both output:
COL1
COL2
a
1
b
1
c
1
a
2
b
2
c
2
a
3
b
3
c
3
db<>fiddle here
You can create "tables" within your query in many different ways, several of which have been illustrated in other answers already.
For your request I like an XML solution as shown below:
create table table1 (col1 varchar2(1));
insert into table1(col1) values('a');
insert into table1(col1) values('b');
insert into table1(col1) values('c');
commit;
select t1.col1, xmlcast(column_value as number) as col2
from table1 t1 cross join xmltable('1 to 3')
;
COL1 COL2
---- ----
a 1
a 2
a 3
b 1
b 2
b 3
c 1
c 2
c 3
How to update rows with a given repeating number sequence.
my table is as follows
line_type
line_val
line_pattern
A
1
null
A
2
null
B
5
null
B
6
null
C
3
null
C
4
null
Now I want to update the column value with the repeating pattern of 8532
So the table after the update will look like
line_type
line_val
line_pattern
A
1
8
A
2
5
B
5
3
B
6
2
C
3
8
C
4
5
How can I achieve this in a update statement ?
With the data you have provided it is not possible to satisfy your requirement. The data in a table is not stored in a specific order. If you want the order to be guaranteed in a select statement, you need to provide an ORDER BY clause.
In the code below there is an additional column "ORDER_BY" to specify the order in which the records need to be processed. The repeating pattern is calculated using the MOD function to convert the row number to a repeating sequence of 4 numbers and then CASE maps each of those numbers to its respective pattern location.
WITH test_data (order_by, line_type, line_val)
AS
(
SELECT 1, 'A',1 FROM DUAL UNION ALL
SELECT 2, 'A',2 FROM DUAL UNION ALL
SELECT 3, 'B',5 FROM DUAL UNION ALL
SELECT 4, 'B',6 FROM DUAL UNION ALL
SELECT 5, 'C',3 FROM DUAL UNION ALL
SELECT 6, 'C',4 FROM DUAL
)
SELECT
CASE MOD(ROW_NUMBER() OVER (ORDER BY order_by),4)
WHEN 1 THEN 8
WHEN 2 THEN 5
WHEN 3 THEN 3
WHEN 0 THEN 2
END as line_pattern,
t.*
FROM
test_data t
LINE_PATTERN ORDER_BY L LINE_VAL
------------ ---------- - ----------
8 1 A 1
5 2 A 2
3 3 B 5
2 4 B 6
8 5 C 3
5 6 C 4
If you don't care about the order then use this form:
UPDATE mytable
SET line_pattern =
CASE MOD (ROWNUM, 4)
WHEN 1 THEN 8
WHEN 2 THEN 5
WHEN 3 THEN 3
WHEN 0 THEN 2
END
Here is the table where ORGID/USERID makes unique combination:
ORGID USERID
1 1
1 2
1 3
1 4
2 1
2 5
2 6
2 7
3 9
3 10
3 11
I need to select all records (organizations and users) wherever USERID 1 is present. So USERID=1 is present in ORGID 1 and 2 so then select all users for these organizations including user 1 itself, i.e.
ORGID USERID
1 1
1 2
1 3
1 4
2 1
2 5
2 6
2 7
Is it possible to do it with one SQL query rather than SELECT *.. WHERE USERID IN (SELECT...
You could use exists:
select *
from mytable t
where exists (select 1 from mytable t1 where t1.orgid = t.orgid and t1.userid = 1)
Another option is window functions. In Postgres:
select *
from (
select t.*,
bool_or(userid = 1) over(partition by orgid) has_user_1
from mytable t
) t
where has_user_1
Or a more generic approach, that uses portable expressions:
select *
from (
select t.*,
max(case when userid = 1 then 1 else 0 end) over(partition by orgid) has_user_1
from mytable t
) t
where has_user_1 = 1
Yes, you can do it with a single select statement - no in or exists conditions, no analytic or aggregate functions in a subquery, etc. Why you want to do it that way is not clear; in any case, it is possible that the solution below is also more efficient than the alternatives. You will have to test on your real-life data to see if that is true.
The solution below has two potential disadvantages: it only works in Oracle (it uses a proprietary extension of SQL, the match_recognize clause); and it only works in Oracle 12.1 or higher.
with
my_table(orgid, userid) as (
select 1, 1 from dual union all
select 1, 2 from dual union all
select 1, 3 from dual union all
select 1, 4 from dual union all
select 2, 1 from dual union all
select 2, 5 from dual union all
select 2, 6 from dual union all
select 2, 7 from dual union all
select 3, 9 from dual union all
select 3, 10 from dual union all
select 3, 11 from dual
)
-- End of SIMULATED data (for testing), not part of the solution.
-- In real life you don't need the WITH clause; reference your actual table.
select *
from my_table
match_recognize(
partition by orgid
all rows per match
pattern (x* a x*)
define a as userid = 1
);
Output:
ORGID USERID
---------- ----------
1 1
1 2
1 3
1 4
2 1
2 5
2 7
2 6
You can use exists:
select ou.*
from orguser ou
where exists (select 1
from orguser ou ou2
where ou2.orgid = ou.orgid and ou2.userid = 1
);
Apart from Exists and windows function, you can use IN as follows:
select *
from your_table t
where t.orgid in (select t1.orgid from your_table t1 where t1.userid = 1)
i want get query from 2 table but show all column overhand
first all column from table 1 Second all column from table 2 then show overhand
table1
----------
a 1 2 3
table2
----------
b 4 5 6
query Result
----------
a 1 2 3
b 4 5 6
Grateful
do you mean:
Select * from table1
Union
Select * from table2
if you want all data no matter they are repetitive or not use UNION ALL otherwise if you want to have unique result use UNION
for example if you had 1 2 3 in table2 the result with UNION will be
1 2 3
and result with UNION ALL will be
1 2 3
1 2 3
Try using UNION in your query:
select * from table1
union all
select * from table2
Assume the following table:
TableA:
ID GroupName SomeValue
1 C 1
2 C 1
2 B 1
2 A 1
I need to construct a query that selects the following result:
ID GroupName SomeValue
1 C 1
1 B 0
1 A 0
2 C 1
2 B 1
2 A 1
The GroupName is actually derived from TableA column's CASE expression and can take only 3 values: A, B, C.
Are the analytic functions the way to go?
EDIT
Sorry, for not mentioning it, but the ID could consist of multiple columns. Consider this example:
ID1 ID2 GroupName SomeValue
1 1 C 1
1 2 C 1
2 2 C 1
2 2 B 1
2 2 A 1
I need to pad SomeValue with 0 for each unique combination ID1+ID2. So the result should be like this:
ID1 ID2 GroupName SomeValue
1 1 C 1
1 1 B 0
1 1 A 0
1 2 C 1
1 2 B 0
1 2 A 0
2 2 C 1
2 2 B 1
2 2 A 1
EDIT2
Seems like solution, proposed by #Laurence should work even for multiple-column 'ID'. I couldn't rewrite the query proposed by #Nicholas Krasnov to conform to this requirement. But could somebody compare these solutions performance-wise? Will the analytic function work faster than 'cross join + left outer join'?
To fill in gaps, you could write a similar query using partition by clause of outer join:
SQL> with t1(ID,GroupName,SomeValue) as
2 (
3 select 1, 'C', 1 from dual union all
4 select 2, 'C', 1 from dual union all
5 select 2, 'B', 1 from dual union all
6 select 2, 'A', 1 from dual
7 ),
8 groups(group_name) as(
9 select 'A' from dual union all
10 select 'B' from dual union all
11 select 'C' from dual
12 )
13 select t1.ID
14 , g.group_name
15 , nvl(SomeValue, 0) SomeValue
16 from t1
17 partition by (t1.Id)
18 right outer join groups g
19 on (t1.GroupName = g.group_name)
20 order by t1.ID asc, g.group_name desc
21 ;
ID GROUP_NAME SOMEVALUE
---------- ---------- ----------
1 C 1
1 B 0
1 A 0
2 C 1
2 B 1
2 A 1
6 rows selected
UPDATE: Response to the comment.
Specify ID2 column in the partition by clause as well:
SQL> with t1(ID1, ID2, GroupName,SomeValue) as
2 (
3 select 1, 1, 'C', 1 from dual union all
4 select 1, 2, 'C', 1 from dual union all
5 select 2, 2, 'C', 1 from dual union all
6 select 2, 2, 'B', 1 from dual union all
7 select 2, 2, 'A', 1 from dual
8 ),
9 groups(group_name) as(
10 select 'A' from dual union all
11 select 'B' from dual union all
12 select 'C' from dual
13 )
14 select t1.ID1
15 , t1.ID2
16 , g.group_name
17 , nvl(SomeValue, 0) SomeValue
18 from t1
19 partition by (t1.Id1, t1.Id2)
20 right outer join groups g
21 on (t1.GroupName = g.group_name)
22 order by t1.ID1, t1.ID2 asc , g.group_name desc
23 ;
ID1 ID2 GROUP_NAME SOMEVALUE
---------- ---------- ---------- ----------
1 1 C 1
1 1 B 0
1 1 A 0
1 2 C 1
1 2 B 0
1 2 A 0
2 2 C 1
2 2 B 1
2 2 A 1
9 rows selected
Select
i.Id1,
i.Id2,
g.GroupName,
Coalesce(a.SomeValue, 0) As SomeValue
From
(select distinct ID1, ID2 from TableA) as i
cross join
(select distinct GroupName from TableA) as g
left outer join
tableA a
on i.ID = a.ID and g.GroupName = a.GroupName
Order By
1,
2,
3 Desc