i have a self related table myTable like :
ID | RefID
----------
1 | NULL
2 | 1
3 | 2
4 | NULL
5 | 2
6 | 5
7 | 5
8 | NULL
9 | 7
i need to get leaf rows on any depth
based on the table above, the result must be :
ID | RefID
----------
3 | 2
4 | NULL
6 | 5
8 | NULL
9 | 7
thank you
PS: the depth may vary , here is very small example
Try:
SELECT id,
refid
FROM mytable t
WHERE NOT EXISTS (SELECT 1
FROM mytable
WHERE refid = t.id)
DECLARE #t TABLE (id int NOT NULL, RefID int NULL);
INSERT #t VALUES (1, NULL), (2, 1), (3, 2), (5, NULL),
(6, 5), (4, NULL), (7, 5), (8, NULL), (9, 8), (10, 7);
WITH CTE AS
(
-- top level
SELECT id, RefID, id AS RootId, 0 AS CTELevel FROM #t WHERE REfID IS NULL
UNION ALL
SELECT T.id, T.RefID, RootId, CTELevel + 1 FROM #t T JOIN CTE ON T.RefID = CTE.id
), Leafs AS
(
SELECT
id, RefID, DENSE_RANK() OVER (PARTITION BY CTE.RootId ORDER BY CTELevel DESC) AS Rn
FROM CTE
)
SELECT
id, RefID
FROM
Leafs
WHERE
rn = 1
select ID, RefId
from myTable t1 left join myTable t2 on t1.ID = t2.RefID
where t2.RefID is null
try this:
SELECT *
FROM
my_table
WHERE
id NOT IN
(
SELECT DISTINCT
refId
FROM
my_table
WHERE
refId IS NOT NULL
)
Related
I saw many questions related to a recursive query but couldn't find any that shows how to use it based on a reference table.
I have a MasterTable where Id, ParentId columns are establishing the parent/child relation.
I have a SubTable where I have a bunch of Ids which could be a parent Id or child Id.
I would like to retrieve all related records (parent or child, recursively) from the MasterTable based on given SubTable
Current output:
id parentId
----------- -----------
1 NULL
2 1
3 1
4 NULL
5 4
6 5
7 6
Expected output
id parentId
----------- -----------
1 NULL
2 1
3 1
4 NULL
5 4
6 5
7 6
8 9
9 NULL
10 NULL
11 10
13 11
14 10
15 16
16 NULL
Comparison of actual vs expected:
Code:
DECLARE #MasterTable TABLE
(
id INT NOT NULL,
parentId INT NULL
);
DECLARE #SubTable TABLE
(
id INT NOT NULL
);
INSERT INTO #MasterTable (id, parentId)
VALUES (1, NULL), (2, 1), (3, 1), (4, NULL), (5, 4), (6, 5),
(7, 6), (8, 9), (9, NULL), (10, NULL), (11, 10), (12, NULL),
(13, 11), (13, 11), (14, 10), (15, 16), (16, NULL);
INSERT INTO #SubTable (id)
VALUES (1), (2), (3), (4), (6), (5), (7),
(8), -- it does not show
(13), -- it does not show
(15); -- it does not show
/* beside 8,13,15 it should add 9,11,14 and 10,16 */
;WITH cte AS
(
SELECT
mt1.id,
mt1.parentId
FROM
#MasterTable AS mt1
WHERE
mt1.parentId IS NULL
AND EXISTS (SELECT NULL AS empty
FROM #SubTable AS st
WHERE st.Id = mt1.id)
UNION ALL
SELECT
mt2.id,
mt2.parentId
FROM
#MasterTable AS mt2
INNER JOIN
cte AS c1 ON c1.id = mt2.parentId
)
SELECT DISTINCT
c2.id,
c2.parentId
FROM
cte AS c2
ORDER BY
id;
Is the following query suitable for the issue in question?
with
r as(
select
m.*, iif(m.parentid is null, 1, 0) p_flag
from #MasterTable m
join #SubTable s
on s.id = m.id
union all
select
m.*, iif(m.parentid is null, 1, r.p_flag)
from r
join #MasterTable m
on (r.p_flag = 1 and m.parentid = r.id) or
(r.p_flag = 0 and r.parentid = m.id)
)
select distinct
id, parentid
from r
order by id;
Output:
| id | parentid |
+----+----------+
| 1 | NULL |
| 2 | 1 |
| 3 | 1 |
| 4 | NULL |
| 5 | 4 |
| 6 | 5 |
| 7 | 6 |
| 8 | 9 |
| 9 | NULL |
| 10 | NULL |
| 11 | 10 |
| 13 | 11 |
| 14 | 10 |
| 15 | 16 |
| 16 | NULL |
Test it online with rextester.com.
;WITH cte
AS (
SELECT mt1.id,
mt1.parentId
FROM #MasterTable AS mt1
WHERE mt1.parentId IS NULL
UNION ALL
SELECT mt2.id,
mt2.parentId
FROM #MasterTable AS mt2
INNER JOIN cte AS c1
ON c1.id = mt2.parentId
)
SELECT DISTINCT c2.id,
c2.parentId
FROM cte AS c2
where
EXISTS (
SELECT 1 AS empty FROM #SubTable AS st
WHERE ( st.Id = c2.id or st.Id = c2.parentId)
)
or
EXISTS (
SELECT 1 AS empty FROM #MasterTable AS mt
WHERE ( c2.Id = mt.parentId or c2.parentId = mt.parentId)
)
ORDER BY id;
You may try this....
; with cte as(
select distinct mas.id, mas.parentId, iif(mas.parentid is null, 1, 0) PId
from #MasterTable mas inner join #SubTable sub
on sub.id in(mas.id, mas.parentid) ----- create top node having parentid is null
union all
select mas.id, mas.parentId, ct.PId
from cte ct inner join #MasterTable mas
on (ct.PId = 1 and mas.parentid = ct.id) or
(ct.PId = 0 and ct.parentid = mas.id) ----- create child node for correspoding parentid created above
)
select distinct id, parentid from cte order by id
option (MAXRECURSION 100); ---- Add Maxrecursion to prevent the infinite loop
You can find this link for more info on recursive query in SQL link. In this link see Example E or above.
I want to select the rows which satisfy both conditions of the same column. Below is the table schema.
Security Table
Id RoleId CompId SecurityToken Accesstype
1 1 10 abc 2
2 1 10 xyz 2
3 12 10 abc 2
4 16 12 abc 2
5 16 12 xyz 2
6 30 13 abc 2
7 1 10 efg 2
8 1 10 lmn 0
I want "All rows for each RoleID/CompID combination where accesstype = 2 and there is both a row containing securitytoken "abc" and a row containing SecurityToken "xyz" for that role/compID combination"
Output should be
Id RoleId CompId SecurityToken Accesstype
1 1 10 abc 2
2 1 10 xyz 2
4 16 12 abc 2
5 16 12 xyz 2
I believe the following query will produce the desired output:
SELECT *
FROM testdata
WHERE Accesstype = 2
AND SecurityToken IN ('abc', 'xyz')
AND EXISTS (
SELECT 1
FROM testdata AS tmp
WHERE RoleId = testdata.RoleId
AND CompId = testdata.CompId
AND Accesstype = testdata.AccessType
AND SecurityToken IN ('abc', 'xyz')
HAVING COUNT(DISTINCT SecurityToken) = 2
)
SQL Fiddle
In order to eliminate sets that contain extra security tokens (such as efg and lmn) change the WHERE and HAVING clause to:
WHERE RoleId = testdata.RoleId
AND CompId = testdata.CompId
AND Accesstype = testdata.AccessType
HAVING COUNT(DISTINCT SecurityToken) = 2
AND COUNT(DISTINCT SecurityToken) = COUNT(CASE WHEN SecurityToken IN ('abc', 'xyz') THEN 1 END)
CREATE TABLE #Table1
([Id] int, [RoleId] int, [CompId] int, [SecurityToken] varchar(3), [Accesstype] int)
;
INSERT INTO #Table1
([Id], [RoleId], [CompId], [SecurityToken], [Accesstype])
VALUES
(1, 1, 10, 'abc', 2),
(2, 1, 10, 'xyz', 2),
(3, 12, 10, 'abc', 2),
(4, 16, 12, 'abc', 2),
(5, 16, 12, 'xyz', 2),
(6, 30, 13, 'abc', 2)
;
WITH cte AS (
SELECT *,ROW_NUMBER() OVER (PARTITION BY [ROLEID],[COMPID] ORDER BY ID) AS RN FROM #TABLE1
),
COUNTED AS (
SELECT
*,
COUNT(*) OVER (PARTITION BY [ROLEID],[COMPID]) AS CNT
FROM cte
)
SELECT
[ID], [ROLEID], [COMPID], [SECURITYTOKEN], [ACCESSTYPE]
FROM COUNTED
WHERE CNT >= 2
output
ID ROLEID COMPID SECURITYTOKEN ACCESSTYPE
1 1 10 abc 2
2 1 10 xyz 2
4 16 12 abc 2
5 16 12 xyz 2
or
WITH CTE AS
(
SELECT
*,
COUNT(*) OVER (PARTITION BY [ROLEID],[COMPID]) AS CNT
FROM #TABLE1)
SELECT [ID], [ROLEID], [COMPID], [SECURITYTOKEN], [ACCESSTYPE] FROM CTE WHERE CNT>=2
One method uses exists:
select t.*
from t
where t.Accesstype = 2 and
t.securityToken in ('abc', 'xyz') and
exists (select 1
from t t2
where t2.RoleId = t.RoleId and
t2.CompId = t.CompId and
t2.Accesstype = t.AccessType and
t2.SecurityToken in ('abc', 'xyz') and
t2.SecrityToken <> t.SecurityToken
);
Perhaps a simpler method uses window functions:
select t.*
from (select t.*,
min(securitytoken) over (partition by roleid, compid) as min_st,
min(securitytoken) over (partition by roleid, compid) as max_st
from t
where t.Accesstype = 2 and
t.SecurityToken in ('abc', 'xyz')
) t
where minsecuritytoken = 'abc' and
maxsecuritytoken = 'xyz;
I have two columns, an ID, and the other a value which is either 0 or 1. I am trying to select all Rows for the ID where it has a 0 and a 1, for example,
RowNumber ------------- ID ------- value
1 ------------------- 001 ------- 1
2 ------------------- 001 ------- 1
3 ------------------- 001 ------- 1
4 ------------------- 002 ------- 1
5 ------------------- 002 ------- 0
6 ------------------- 003 ------- 1
7 ------------------- 003 ------- 1
8 --------------------004 ------- 1
9 -------------------- 004 ------- 0
10 ------------------- 004 ------- 1
The result should select rows 4, 5, 8, 9, 10
You can use window version of COUNT:
SELECT RowNumber, ID, value
FROM (
SELECT RowNumber, ID, value,
COUNT(CASE WHEN value = 1 THEN 1 END) OVER (PARTITION BY ID) AS cntOnes,
COUNT(CASE WHEN value = 0 THEN 1 END) OVER (PARTITION BY ID) AS cntZeroes
FROM test
WHERE value IN (0,1) ) AS t
WHERE cntOnes >= 1 AND cntZeroes >= 1
COUNT(DISTINCT value) has a value of 2 if both 0, 1 values exist within the same ID slice.
DISTINCT is indeed not allowed in a windowed version of the COUNT, so you can use MIN and MAX instead.
DECLARE #T TABLE(RN int, ID int, value int);
INSERT INTO #T (RN, ID, value) VALUES
(1, 001, 1),
(2, 001, 1),
(3, 001, 1),
(4, 002, 1),
(5, 002, 0),
(6, 003, 1),
(7, 003, 1),
(8, 004, 1),
(9, 004, 0),
(10, 004, 1);
WITH
CTE
AS
(
SELECT
RN, ID, value
,MIN(value) OVER (PARTITION BY ID) AS MinV
,MAX(value) OVER (PARTITION BY ID) AS MaxV
FROM #T AS T
)
SELECT RN, ID, value
FROM CTE
WHERE MinV <> MaxV
;
Result
+----+----+-------+
| RN | ID | value |
+----+----+-------+
| 4 | 2 | 1 |
| 5 | 2 | 0 |
| 8 | 4 | 1 |
| 9 | 4 | 0 |
| 10 | 4 | 1 |
+----+----+-------+
create table #shadowTemp (
RowNumber int not null,
Id char(3) not null,
value bit not null
)
insert into #shadowTemp values ( 1,'001', 0 )
insert into #shadowTemp values ( 2,'001', 1 )
insert into #shadowTemp values ( 3,'001', 1 )
insert into #shadowTemp values ( 4,'002', 0 )
insert into #shadowTemp values ( 5,'003', 0 )
insert into #shadowTemp values ( 6,'003', 1 )
select * from #shadowTemp;
;with cte ( Id ) As (
select Id
from #shadowTemp
group by Id
having sum( value + 1 ) >= 3
)
select a.*
from
#shadowTemp a
inner join cte b on ( a.Id = b.Id )
drop table #shadowTemp
I have a table like so
ID Node ParentID
1 A 0
2 B 1
3 C 1
4 D 2
5 E 2
6 F 3
7 G 3
8 H 3
9 I 4
10 J 4
11 K 10
12 L 11
I need a query to generate a 'level' field that shows how many levels deep a particular node is. Example below
ID Node ParentID Level
1 A 0 1
2 B 1 2
3 C 1 2
4 D 2 3
5 E 2 3
6 F 3 4
7 G 3 4
8 H 3 4
9 I 4 5
10 J 4 5
11 K 10 6
12 L 11 7
Select Id,
Node,
ParentID,
Dense_Rank() Over(Order by ParentID) as Level
from Table_Name
SQL Fiddle Demo
You can use DENSE_RANK function
SELECT i.ID, p.Node, i.ParentID
,Dense_Rank() Over(Order by ParentID) as Level
FROM TableName AS i;
for more detail visit: http://blog.sqlauthority.com/2007/10/09/sql-server-2005-sample-example-of-ranking-functions-row_number-rank-dense_rank-ntile/
I think the correct way to do it will be to get the parent level and increment it by 1 when inserting the data since all other ways are expensive performance wise.
Something like:
;with tree (ID, ParentID, Level)
as (
select ID, ParentID, 1 from TableName where ParentID = 0
union all
select t.ID, t.ParentID, 1 + tree.Level
from Tree join TableName t on t.ParentID = Tree.ID
)
select ID, Level from Tree
Try this
CREATE TABLE #Table1
([ID] int, [Node] varchar(1), [ParentID] int)
;
INSERT INTO #Table1
([ID], [Node], [ParentID])
VALUES
(1, 'A', 0),
(2, 'B', 1),
(3, 'C', 1),
(4, 'D', 2),
(5, 'E', 2),
(6, 'F', 3),
(7, 'G', 3),
(8, 'H', 3),
(9, 'I', 4),
(10, 'J', 4),
(11, 'K', 10),
(12, 'L', 11)
;
;WITH CTE ([ID], [ParentID], [Node], [Level])
as (
SELECT [ID], [ParentID], [Node], 1 FROM #Table1 WHERE ParentID = 0
UNION all
select t.[ID], t.[ParentID], t.[Node], 1 + c.[Level]
from CTE c inner join #Table1 t ON t.[ParentID] = c.[ID]
)
select ID, [Node], [ParentID], [Level] from CTE
ORDER BY [Node]
DROP TABLE #Table1
Here, you need to set level by grouping ParentID then join both tables by ParentID.
WITH CTE (ParentID, Level)
AS (
SELECT ParentID
, Row_Number() OVER (ORDER BY ParentID) AS Level
FROM Table1
GROUP BY ParentID
)
SELECT t1.ID, t1.Node, t1.ParentID, CTE.Level
FROM Table1 t1
JOIN CTE ON t1.ParentID = CTE.ParentID;
See this SQLFiddle
Update: (for MySQL - just to help others)
To do the same in MySQL try to get row number like this:
SELECT t1.ID, t1.Node, t1.ParentID, Tbl.Level
FROM Table1 t1
JOIN
(
SELECT #Level:=#Level+1 AS Level , ParentID
FROM (SELECT DISTINCT ParentID FROM Table1) t
, (SELECT #Level:=0) r
ORDER BY ParentID
) Tbl
ON t1.ParentID = Tbl.ParentID;
See this SQLFiddle
I have a table with an id as the primary key, and a description as another field.
I want to first select the records that have the id<=4, sorted by description, then I want all the other records (id>4), sorted by description. Can't get there!
select id, descr
from t
order by
case when id <= 4 then 0 else 1 end,
descr
select *, id<=4 as low from table order by low, description
You may want to use an id <= 4 expression in your ORDER BY clause:
SELECT * FROM your_table ORDER BY id <= 4 DESC, description;
Test case (using MySQL):
CREATE TABLE your_table (id int, description varchar(50));
INSERT INTO your_table VALUES (1, 'c');
INSERT INTO your_table VALUES (2, 'a');
INSERT INTO your_table VALUES (3, 'z');
INSERT INTO your_table VALUES (4, 'b');
INSERT INTO your_table VALUES (5, 'g');
INSERT INTO your_table VALUES (6, 'o');
INSERT INTO your_table VALUES (7, 'c');
INSERT INTO your_table VALUES (8, 'p');
Result:
+------+-------------+
| id | description |
+------+-------------+
| 2 | a |
| 4 | b |
| 1 | c |
| 3 | z |
| 7 | c |
| 5 | g |
| 6 | o |
| 8 | p |
+------+-------------+
8 rows in set (0.00 sec)
Related post:
Using MySql, can I sort a column but have 0 come last?
select id, description
from MyTable
order by case when id <= 4 then 0 else 1 end, description
You can use UNION
SELECT * FROM (SELECT * FROM table1 WHERE id <=4 ORDER by description)aaa
UNION
SELECT * FROM (SELECT * FROM table1 WHERE id >4 ORDER by description)bbb
OR
SELECT * FROM table1
ORDER BY
CASE WHEN id <=4 THEN 0
ELSE 1
END, description