Suppose I have a table like this:
Id Types Timestamp
1 A 2014-02-04 00:00:00
2 A 2014-02-05 00:00:00
1 A 2014-02-05 03:59:00
3 C 2014-05-06 03:59:00
1 B 2014-02-04 03:00:00
2 D 2014-02-05 00:40:00
I would like the output to be like this:
Id 1 2 3 4 5 etc
1 A B A C D ...
2 A D NULL NULL NULL
3 C NULL NULL NULL NULL
Is it possible to make time expresses the type's order.
Thanks for any hints.
Preliminary comments:
SQL can only return a predefined number of columns returned. IMHO, the best you can get is values concatenated in an array.
I have name your input table MyTable and renamed the column Timestamp to MyTimestamp to avoid conflict with the corresponding type's keyword.
You have put C and D in the 1 row of your output. I will treat it as a typo (they are not on ID = 1)
-
WITH RECURSIVE ConcatAndOrder(ID, MyResult, RowNumForOrder, RowCountForOrder) AS (
SELECT ID, ARRAY[Type], RowNumForOrder, RowCountForOrder
FROM IndexedTable
WHERE RowNumForOrder = 1
UNION ALL
SELECT I.ID, MyResult || I.Type, I.RowNumForOrder, I.RowCountForOrder
FROM IndexedTable I
JOIN ConcatAndOrder C on I.ID = C.ID and I.RowNumForOrder = C.RowNumForOrder + 1
), IndexedTable(ID, Type, RowNumForOrder, RowCountForOrder) AS (
SELECT ID, Type,
row_number() OVER (PARTITION BY ID ORDER BY MyTimestamp),
count(*) OVER (PARTITION BY ID)
FROM MyTable
)
SELECT ID, MyResult
FROM ConcatAndOrder
WHERE RowNumForOrder = RowCountForOrder
ORDER BY ID
Related
I have table with self-related foreign keys and can not get how I can receive firs child or descendant which meet condition. My_table structure is:
id
parent_id
type
1
null
union
2
1
group
3
2
group
4
3
depart
5
1
depart
6
5
unit
7
1
unit
I should for id 1 (union) receive all direct child or first descendant, excluding all groups between first descendant and union. So in this example as result I should receive:
id
type
4
depart
5
depart
7
unit
id 4 because it's connected to union through group with id 3 and group with id 2 and id 5 because it's connected directly to union.
I've tried to write recursive query with condition for recursive part: when parent_id = 1 or parent_type = 'depart' but it doesn't lead to expected result
with recursive cte AS (
select b.id, p.type_id
from my_table b
join my_table p on p.id = b.parent_id
where b.id = 1
union
select c.id, cte.type_id
from my_table c
join cte on cte.id = c.parent_id
where c.parent_id = 1 or cte.type_id = 'group'
)
Here's my interpretation:
if type='group', then id and parent_id are considered in the same group
id#1 and id#2 are in the same group, they're equals
id#2 and id#3 are in the same group, they're equals
id#1, id#2 and id#3 are in the same group
If the above is correct, you want to get all the first descendent of id#1's group. The way to do that:
Get all the ids in the same group with id#1
Get all the first descendants of the above group (type not in ('union', 'group'))
with recursive cte_group as (
select 1 as id
union all
select m.id
from my_table m
join cte_group g
on m.parent_id = g.id
and m.type = 'group')
select mt.id,
mt.type
from my_table mt
join cte_group cg
on mt.parent_id = cg.id
and mt.type not in ('union','group');
Result:
id|type |
--+------+
4|depart|
5|depart|
7|unit |
Sounds like you want to start with the row of id 1, then get its children, and continue recursively on rows of type group. To do that, use
WITH RECURSIVE tree AS (
SELECT b.id, b.type, TRUE AS skip
FROM my_table b
WHERE id = 1
UNION ALL
SELECT c.id, c.type, (c.type = 'group') AS skip
FROM my_table c
JOIN tree p ON c.parent_id = p.id AND p.skip
)
SELECT id, type
FROM tree
WHERE NOT skip
In my postgres table, I have two columns of interest: id and name - my goal is to only keep records where id has more than one value in name. In other words, would like to keep all records of ids that have multiple values and where at least one of those values is B
UPDATE: I have tried adding WHERE EXISTS to the queries below but this does not work
The sample data would look like this:
> test
id name
1 1 A
2 2 A
3 3 A
4 4 A
5 5 A
6 6 A
7 7 A
8 2 B
9 1 B
10 2 B
and the output would look like this:
> output
id name
1 1 A
2 2 A
8 2 B
9 1 B
10 2 B
How would one write a query to select only these kinds records?
Based on your description you would seem to want:
select id, name
from (select t.*, min(name) over (partition by id) as min_name,
max(name) over (partition by id) as max_name
from t
) t
where min_name < max_name;
This can be done using EXISTS:
select id, name
from test t1
where exists (select *
from test t2
where t1.id = t2.id
and t1.name <> t2.name) -- this will select those with multiple names for the id
and exists (select *
from test t3
where t1.id = t3.id
and t3.name = 'B') -- this will select those with at least one b for that id
Those records where for their id more than one name shines up, right?
This could be formulated in "SQL" as follows:
select * from table t1
where id in (
select id
from table t2
group by id
having count(name) > 1)
for example i have column that look like this:
name | id | value
A 1 aa
A 2 ab
B 3 bc
C 4 ca
C 5 cb
Is there any way to change it to this ?
name | id | value
A 1 aa
A 1 ab
B 3 bc
C 4 ca
C 4 cb
You can do this with a window function that numbers the rows, and use that select statement to supply the values for the update:
update the_table
set id = t.rn
from (
select name,
id,
dense_rank() over (order by name) as rn
from the_table
) t
where (t.name, t.id) = (the_table.name, the_table.id);
SQLFiddle example: http://sqlfiddle.com/#!15/0e987/1
This assumes that the existing combination (id, name) is unique. If that is not the case, you would need to use the ctid column to match the rows between the inner select and the table itself:
update the_table
set id = t.rn
from (
select name,
id,
ctid,
dense_rank() over (order by name) as rn
from the_table
) t
where t.ctid = the_table.ctid;
I have tables with following structure
create table Doc(
id int identity(1, 1) primary key,
DocumentStartValue varchar(100)
)
create Metadata (
DocumentValue varchar(100),
StartDesignation char(1),
PageNumber int
)
GO
Doc contains
id DocumentStartValue
1000 ID-1
1100 ID-5
2000 ID-8
3000 ID-9
Metadata contains
Documentvalue StartDesignation PageNumber
ID-1 D 0
ID-2 NULL 1
ID-3 NULL 2
ID-4 NULL 3
ID-5 D 0
ID-6 NULL 1
ID-7 NULL 2
ID-8 D 0
ID-9 D 0
What I need to is to map Metadata.DocumentValues to Doc.id
So the result I need is something like
id DocumentValue PageNumber
1000 ID-1 0
1000 ID-2 1
1000 ID-3 2
1000 ID-4 3
1100 ID-5 0
1100 ID-6 1
1100 ID-7 2
2000 ID-8 0
3000 ID-9 0
Can it be achieved without the use of cursor?
Something like, sorry can't test
;WITH RowList AS
( --assign RowNums to each row...
SELECT
ROW_NUMBER() OVER (ORDER BY id) AS RowNum,
id, DocumentStartValue
FROM
doc
), RowPairs AS
( --this allows us to pair a row with the previous rows to create ranges
SELECT
R.DocumentStartValue AS Start, R.id,
R1.DocumentStartValue AS End
FROM
RowList R JOIN RowList R1 ON R.RowNum + 1 = R1.RowNum
)
--use ranges to join back and get the data
SELECT
RP.id, M.DocumentValue, M.PageNumber
FROM
RowPairs RP
JOIN
Metadata M ON RP.Start <= M.DocumentValue AND M.DocumentValue < RP.End
Edit: This assumes that you can rely on the ID-x values matching and being ascending. If so, StartDesignation is superfluous/redundant and may conflict with the Doc table DocumentStartValue
with rm as
(
select DocumentValue
,PageNumber
,case when StartDesignation = 'D' then 1 else 0 end as IsStart
,row_number() over (order by DocumentValue) as RowNumber
from Metadata
)
,gm as
(
select
DocumentValue as DocumentGroup
,DocumentValue
,PageNumber
,RowNumber
from rm
where RowNumber = 1
union all
select
case when rm.IsStart = 1 then rm.DocumentValue else gm.DocumentGroup end
,rm.DocumentValue
,rm.PageNumber
,rm.RowNumber
from gm
inner join rm on rm.RowNumber = (gm.RowNumber + 1)
)
select d.id, gm.DocumentValue, gm.PageNumber
from Doc d
inner join gm on d.DocumentStartValue = gm.DocumentGroup
Try to use query above (maybe you will need to add option (maxrecursion ...) also) and add index on DocumentValue for Metadata table. Also, it it's possible - it will be better to save appropriate group on Metadat rows inserting.
UPD: I've tested it and fixed errors in my query, not it works and give result as in initial question.
UPD2: And recommended indexes:
create clustered index IX_Metadata on Metadata (DocumentValue)
create nonclustered index IX_Doc_StartValue on Doc (DocumentStartValue)
My table is like
ID FName LName Date(mm/dd/yy) Sequence Value
101 A B 1/10/2010 1 10
101 A B 1/10/2010 2 20
101 X Y 1/2/2010 1 15
101 Z X 1/3/2010 5 10
102 A B 1/10/2010 2 10
102 X Y 1/2/2010 1 15
102 Z X 1/3/2010 5 10
I need a query that should return 2 records
101 A B 1/10/2010 2 20
102 A B 1/10/2010 2 10
that is max of date and max of sequence group by id.
Could anyone assist on this.
-----------------------
-- get me my rows...
-----------------------
select * from myTable t
-----------------------
-- limiting them...
-----------------------
inner join
----------------------------------
-- ...by joining to a subselection
----------------------------------
(select m.id, m.date, max(m.sequence) as max_seq from myTable m inner join
----------------------------------------------------
-- first group on id and date to get max-date-per-id
----------------------------------------------------
(select id, max(date) as date from myTable group by id) y
on m.id = y.id and m.date = y.date
group by id) x
on t.id = x.id
and t.sequence = x.max_seq
Would be a simple solution, which does not take account of ties, nor of rows where sequence is NULL.
EDIT: I've added an extra group to first select max-date-per-id, and then join on this to get max-sequence-per-max-date-per-id before joining to the main table to get all columns.
I have considered your table name as employee..
check the below thing helped you.
select * from employee emp1
join (select Id, max(Date) as dat, max(sequence) as seq from employee group by id) emp2
on emp1.id = emp2.id and emp1.sequence = emp2.seq and emp1.date = emp2.dat
I'm a fan of using the WITH clause in SELECT statements to organize the different steps. I find that it makes the code easier to read.
WITH max_date(max_date)
AS (
SELECT MAX(Date)
FROM my_table
),
max_seq(max_seq)
AS (
SELECT MAX(Sequence)
FROM my_table
WHERE Date = (SELECT md.max_date FROM max_date md)
)
SELECT *
FROM my_table
WHERE Date = (SELECT md.max_date FROM max_date md)
AND Sequence = (SELECT ms.max_seq FROM max_seq ms);
You should be able to optimize this further as needed.