T-SQL Some questions about a recursive query (CTE) - tsql

I take all items (e.g advertisements) from a tree using CTE (here), but I'm wondering about two things - the hardest part:
1) is it somehow possible to get all category names of the found advertisements ? (in the recursive CTE query, look at the hyperlink above)
2) And (optional) how to get the total found advertisement's count of the each category ? I mean, let's say I found 6 items from 3 categories and I'd like to see the result in that way
category1 (6) -\
| category3 (4)
category2 (2)
Any ideas will be so helpful

for the first question you need to go from down to up, it could be resolved with changing querying order ex:
with CTE (id, pid, name)
as
(
select id, parentid as pid,name
from category
where id = #lowLevelCategory
union all
select CTE.pid as id , category.parentid as pid, category.name
from CTE
inner join category
on category.id = CTE.pid
)
select * from ss
for the second one: you can calculate only count of sub items, but not summ and you need some function for this calculations, because grouping or subselecting can't be in recursive part

Related

Union which excludes values from the first table

The origional problem I am attempting to solve is that I need to show all rows from a specific "joined" table. However these are sometimes blank with no totals and normally would not show (think categories and counts for each).
So what I am attempting to do is union to a "0 value" data set to show all categories. However when I do the union it shows a 0 value row, as well as the normal data. Here is an example..
SELECT category_name, COUNT(files_number)
FROM files
LEFT JOIN categories ON categories.category_id = files.category_id
UNION
SELECT category_name, 0
FROM categories
This will give me a result set that looks similar to this:
category_name | value
----------------------
open file | 0
open file | 23
closed file | 0
Is there any way to remove duplicate zero value entries? Please not there is also a complex WHERE clause in the actual query, so avoiding duplication on it is preferred.
I don't get why you are doing left join and union..
You can do below to remove duplicates,wrap your query and do group by
;with cte
as
(
SELECT category_name, COUNT(files_number)
FROM files
LEFT JOIN categories ON categories.category_id = files.category_id
UNION
SELECT category_name, 0
FROM categories
)
select categoryname,sum(aggcol)
from cte
group by
category
One way is to select all categories from the categories table, and LEFT JOIN onto the file counts (grouped by category_id).
SELECT c.category_name, ISNULL(fc.FileCount, 0) AS FileCount
FROM categories c
LEFT JOIN (
SELECT category_id, COUNT(files_number) AS FileCount
FROM files
GROUP BY category_id
) fc ON c.category_id = fc.category_id
Edit
If you want to reverse the query, you could do it something like this, using a RIGHT OUTER JOIN - so every category from categories table is returned, regardless of if there are any files for it:
SELECT c.category_name, COUNT(f.category_id) AS FileCount
FROM files f
RIGHT JOIN categories c ON c.category_id = f.category_id
GROUP BY c.name

Identifying rows with multiple IDs linked to a unique value

Using ms-sql 2008 r2; am sure this is very straightforward. I am trying to identify where a unique value {ISIN} has been linked to more than 1 Identifier. An example output would be:
isin entity_id
XS0276697439 000BYT-E
XS0276697439 000BYV-E
This is actually an error and I want to look for other instances where there may be more than one entity_id linked to a unique ISIN.
This is my current working but it's obviously not correct:
select isin, entity_id from edm_security_entity_map
where isin is not null
--and isin = ('XS0276697439')
group by isin, entity_id
having COUNT(entity_id) > 1
order by isin asc
Thanks for your help.
Elliot,
I don't have a copy of SQL in front of me right now, so apologies if my syntax isn't spot on.
I'd start by finding the duplicates:
select
x.isin
,count(*)
from edm_security_entity_map as x
group by x.isin
having count(*) > 1
Then join that back to the full table to find where those duplicates come from:
;with DuplicateList as
(
select
x.isin
--,count(*) -- not used elsewhere
from edm_security_entity_map as x
group by x.isin
having count(*) > 1
)
select
map.isin
,map.entity_id
from edm_security_entity_map as map
inner join DuplicateList as dup
on dup.isin = map.isin;
HTH,
Michael
So you're saying that if isin-1 has a row for both entity-1 and entity-2 that's an error but isin-3, say, linked to entity-3 in two separe rows is OK? The ugly-but-readable solution to that is to pre-pend another CTE on the previous solution
;with UniqueValues as
(select distinct
y.isin
,y.entity_id
from edm_security_entity_map as y
)
,DuplicateList as
(
select
x.isin
--,count(*) -- not used elsewhere
from UniqueValues as x
group by x.isin
having count(*) > 1
)
select
map.isin
,map.entity_id
from edm_security_entity_map as map -- or from UniqueValues, depening on your objective.
inner join DuplicateList as dup
on dup.isin = map.isin;
There are better solutions with additional GROUP BY clauses in the final query. If this is going into production I'd be recommending that. Or if your table has a bajillion rows. If you just need to do some analysis the above should suffice, I hope.

Simple SELECT, but adding JOIN returns too many rows

The query below returns 9,817 records. Now, I want to SELECT one more field from another table. See the 2 lines that are commented out, where I've simply selected this additional field and added a JOIN statement to bind this new columns. With these lines added, the query now returns 649,200 records and I can't figure out why! I guess something is wrong with my WHERE criteria in conjunction with the JOIN statement. Please help, thanks.
SELECT DISTINCT dbo.IMPORT_DOCUMENTS.ITEMID, BEGDOC, BATCHID
--, dbo.CATEGORY_COLLECTION_CATEGORY_RESULTS.CATEGORY_ID
FROM IMPORT_DOCUMENTS
--JOIN dbo.CATEGORY_COLLECTION_CATEGORY_RESULTS ON
dbo.CATEGORY_COLLECTION_CATEGORY_RESULTS.ITEMID = dbo.IMPORT_DOCUMENTS.ITEMID
WHERE (BATCHID LIKE 'IC0%' OR BATCHID LIKE 'LP0%')
AND dbo.IMPORT_DOCUMENTS.ITEMID IN
(SELECT dbo.CATEGORY_COLLECTION_CATEGORY_RESULTS.ITEMID FROM
CATEGORY_COLLECTION_CATEGORY_RESULTS
WHERE SCORE >= .7 AND SCORE <= .75 AND CATEGORY_ID IN(
SELECT CATEGORY_ID FROM CATEGORY_COLLECTION_CATS WHERE COLLECTION_ID IN (11,16))
AND Sample_Id > 0)
AND dbo.IMPORT_DOCUMENTS.ITEMID NOT IN
(SELECT ASSIGNMENT_FOLDER_DOCUMENTS.Item_Id FROM ASSIGNMENT_FOLDER_DOCUMENTS)
One possible reason is because one of your tables contains data at lower level, lower than your join key. For example, there may be multiple records per item id. The same item id is repeated X number of times. I would fix the query like the below. Without data knowledge, Try running the below modified query.... If output is not what you're looking for, convert it into SELECT Within a Select...
Hope this helps....
Try this SQL: SELECT DISTINCT a.ITEMID, a.BEGDOC, a.BATCHID, b.CATEGORY_ID FROM IMPORT_DOCUMENTS a JOIN (SELECT DISTINCT ITEMID FROM CATEGORY_COLLECTION_CATEGORY_RESULTS WHERE SCORE >= .7 AND SCORE <= .75 AND CATEGORY_ID IN (SELECT DISTINCT CATEGORY_ID FROM CATEGORY_COLLECTION_CATS WHERE COLLECTION_ID IN (11,16)) AND Sample_Id > 0) B ON a.ITEMID =b.ITEMID WHERE a.(a.BATCHID LIKE 'IC0%' OR a.BATCHID LIKE 'LP0%') AND a.ITEMID NOT IN (SELECT DIDTINCT Item_Id FROM ASSIGNMENT_FOLDER_DOCUMENTS)

SSRS 2005 column chart: show series label missing when data count is zero

I have a pretty simple chart with a likely common issue. I've searched for several hours on the interweb but only get so far in finding a similar situation.
the basics of what I'm pulling contains a created_by, person_id and risk score
the risk score can be:
1 VERY LOW
2 LOW
3 MODERATE STABLE
4 MODERATE AT RISK
5 HIGH
6 VERY HIGH
I want to get a headcount of persons at each risk score and display a risk count even if there is a count of 0 for that risk score but SSRS 2005 likes to suppress zero counts.
I've tried this in the point labels
=IIF(IsNothing(count(Fields!person_id.value)),0,count(Fields!person_id.value))
Ex: I'm missing values for "1 LOW" as the creator does not have any "1 LOW" they've assigned risk scores for.
*here's a screenshot of what I get but I'd like to have a column even for a count when it still doesn't exist in the returned results.
#Nathan
Example scenario:
select professor.name, grades.score, student.person_id
from student
inner join grades on student.person_id = grades.person_id
inner join professor on student.professor_id = professor.professor_id
where
student.professor_id = #professor
Not all students are necessarily in the grades table.
I have a =Count(Fields!person_id.Value) for my data points & series is grouped on =Fields!score.Value
If there were a bunch of A,B,D grades but no C & F's how would I show labels for potentially non-existent counts
In your example, the problem is that no results are returned for grades that are not linked to any students. To solve this ideally there would be a table in your source system which listed all the possible values of "score" (e.g. A - F) and you would join this into your query such that at least one row was returned for each possible value.
If such a table doesn't exist and the possible score values are known and static, then you could manually create a list of them in your query. In the example below I create a subquery that returns a combination of all professors and all possible scores (A - F) and then LEFT join this to the grades and students tables (left join means that the professor/score rows will be returned even if no students have those scores in the "grades" table).
SELECT
professor.name
, professorgrades.score
, student.person_id
FROM
(
SELECT professor_id, score
FROM professor
CROSS JOIN
(
SELECT 'A' AS score
UNION
SELECT 'B'
UNION
SELECT 'C'
UNION
SELECT 'D'
UNION
SELECT 'E'
UNION
SELECT 'F'
) availablegrades
) professorgrades
INNER JOIN professor ON professorgrades.professor_id = professor.professor_id
LEFT JOIN grades ON professorgrades.score = grades.score
LEFT JOIN student ON grades.person_id = student.person_id AND
professorgrades.professor_id = student.professor_id
WHERE professorgrades.professor_id = 1
See a live example of how this works here: SQLFIDDLE
SELECT RS.RiskScoreId, RS.Description, SUM(DT.RiskCount) AS RiskCount
FROM (
SELECT RiskScoreId, 1 AS RiskCount
FROM People
UNION ALL
SELECT RiskScoreId, 0 AS RiskCount
FROM RiskScores
) DT
INNER JOIN RiskScores RS ON RS.RiskScoreId = DT.RiskScoreId
GROUP BY RS.RiskScoreId, RS.Description
ORDER BY RS.RiskScoreId

t-sql return multiple rows depending on field value

i am trying to run an export on a system that only allows t-sql. i know enough of php to make a foreach loop, but i don't know enough of t-sql to generate multiple rows for a given quantity.
i need a result to make a list of items with "1 of 4" like data included in the result
given a table like
orderid, product, quantity
1000,ball,3
1001,bike,4
1002,hat,2
how do i get a select query result like:
orderid, item_num, total_items,
product
1000,1,3,ball
1000,2,3,ball
1000,3,3,ball
1001,1,4,bike
1001,2,4,bike
1001,3,4,bike
1001,4,4,bike
1002,1,2,hat
1002,2,2,hat
You can do this with the aid of an auxiliary numbers table.
;WITH T(orderid, product, quantity) AS
(
select 1000,'ball',3 union all
select 1001,'bike',4 union all
select 1002,'hat',2
)
SELECT orderid, number as item_num, quantity as total_items, product
FROM T
JOIN master..spt_values on number> 0 and number <= quantity
where type='P'
NB: The code above uses the master..spt_values table - this is just for demo purposes I suggest you create your own tally table using one of the techniques here.
If you are on SQL Server 2005 or later version, then you can try a recursive CTE instead of a tally table.
;WITH CTE AS
(
SELECT orderid, 1 item_num, product, quantity
FROM YourTable
UNION ALL
SELECT orderid, item_num+1, product, quantity
FROM CTE
WHERE item_num < quantity
)
SELECT *
FROM CTE
OPTION (MAXRECURSION 0)
I'm not on a computer with a database engine where I can test this, so let me know how it goes.
Well, IF you know the maximum value for the # of products for any product (and it's not too big, say 4), you can:
Create a helper table called Nums containing 1 integer column n, with rows containing 1,2,3,4
Run
SELECT * from Your_table, Nums
WHERE Nums.n <= Your_table.quantity