I have a table, lets call it Assemblies. This table has items and components of those items. Further, each of those components might be listed as an item with their own components, creating a list of sub assemblies.
Here's my sql fiddle.
http://sqlfiddle.com/#!3/ec9e9/1
In this example, part A1000 contains h123, which contains T4000, which contains z123. There is another part that is not part of that assembly. Is there a way to design a query that will drill down into each sub assembly of A1000 until there are none left, without having to define how many sub assemblies are nested?
The result would look like this:
item component qty
A1000 h123 4
h123 T4000 7
T4000 z123 2
z123 f2222 4
omitting only what's not in the main assembly A1000
A recursive Common Table Expression (cte) works well for something like this.
How about this?
;WITH cteAssemblies (item, component, qty, AssemblyLevel)
AS
( SELECT
item, component, qty, 1
FROM
dbo.Assemblies b
WHERE
item = 'A1000'
UNION ALL
SELECT
e.item, e.component, e.qty, r.AssemblyLevel + 1
FROM
dbo.Assemblies e
INNER JOIN
cteAssemblies r ON e.item = r.component
)
SELECT item, component, qty FROM cteAssemblies
Above CTE created as a function.
CREATE FUNCTION dbo.FN_GetAssemblyChildren ( #item CHAR(30))
RETURNS TABLE
AS
RETURN
(
WITH cteAssemblies (item, component, qty, AssemblyLevel)
AS
( SELECT
item, component, qty, 1
FROM
dbo.Assemblies b
WHERE
item = #item
UNION ALL
SELECT
e.item, e.component, e.qty, r.AssemblyLevel + 1
FROM
dbo.Assemblies e
INNER JOIN
cteAssemblies r ON e.item = r.component
)
SELECT item, component, qty FROM cteAssemblies
);
GO
Query function
SELECT * FROM dbo.FN_GetAssemblyChildren ('A1000')
Related
Input data
I have the following association table:
AssociationTable
- Item ID: Integer
- Tag ID: Integer
Referring to the following example data
Item Tag
1 1
1 2
1 3
2 1
and some input list of tags T (e.g. [1, 2])
What I want
For each item, I would like to know which tags were not provided in the input list T.
With our sample data, we'd get:
Item Num missing
1 1
2 0
My thoughts
The best I've done so far is: select "ItemId", count("TagId") as "Num missing" from "AssociationTab" where "TagId" not in (1) group by "ItemId";
The problem here is that items where all tags match will not be included in the output.
You could use a calendar table with anti-join approach:
WITH cte AS (
SELECT t1.Item, t2.Tag
FROM (SELECT DISTINCT Item FROM AssociationTable) t1
CROSS JOIN (SELECT 1 AS Tag UNION ALL SELECT 2) t2
)
SELECT
t1.Item,
COUNT(*) FILTER (WHERE t2.Item IS NULL) AS num_missing
FROM cte t1
LEFT JOIN AssociationTable t2
ON t1.Item = t2.Item AND
t1.Tag = t2.Tag AND
t2.Tag IN (1, 2)
GROUP BY
t1.Item;
Demo
The strategy here is to build a calendar/reference table in the first CTE which contains all combinations of items and tags. Then, we left join this CTE to your association table, aggregate by item, and then detect how many tags are missing for each item.
Simplest solution is
SELECT
ItemId,
count(*) FILTER (WHERE TagId NOT IN (1,2))
FROM AssociationTab
GROUP BY ItemId
Alternatively, if you already have an Items table with the item list, you could do this:
SELECT
i.ItemId,
count(a.TagId)
FROM Items i
LEFT JOIN AssociationTab a ON a.ItemId = i.ItemId AND a.TagId NOT IN (1,2)
GROUP BY i.ItemId
The key is that LEFT JOIN does not remove the Items row if no tags match.
I have a temp table with multiple rows in it and each row has a column called Categories; which contains a very simple json array of ids for categories in a different table.
A few example rows of the temp table:
Id Name Categories
---------------------------------------------------------------------------------------------
'539f7e28-143e-41bb-8814-a7b93b846007' Test 1 ["category1Id", "category2Id", "category3Id"]
'f29e2ecf-6e37-4aa9-aa56-4a351d298bfc' Test 2 ["category1Id", "category2Id"]
'34e41a0a-ad92-4cd7-bf5c-8df6bfd6ed5c' Test 3 NULL
Now what I would like to do is to select all of the category ids from all of the rows in the temp table.
What I have is the following and it's not working as it's giving me the error of :
Subquery returned more than 1 value. This is not permitted when the subquery follows =, !=, <, <= , >, >= or when the subquery is used as an expression.
SELECT
c.Id
,c.[Name]
,c.Color
FROM
dbo.Category as c
WHERE
c.Id in (SELECT [value] FROM OPENJSON((SELECT Categories FROM #TempTable)))
and c.IsDeleted = 0
Which I guess it makes sense that's failing on that because I'm selecting multiple rows and needing to parse each row's respective category ids json. I'm just not sure what to do/change to give me the results that I want. Thank you in advance for any help.
You'd need to use CROSS APPLY like so:
SELECT id ,
name ,
t.Value AS category_id
FROM #temp
CROSS APPLY OPENJSON(categories, '$') t;
And then, you can JOIN to your Categories table using the category_id column, something like this:
SELECT id ,
name ,
t.Value AS category_id,
c.*
FROM #temp
CROSS APPLY OPENJSON(categories, '$') t
LEFT JOIN Categories c ON c.Id = t.Value
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
I have a tree structure table with columns:
id,parent,name.
Given a tree A->B->C,
how could i get the most top parent A's ID according to C's ID?
Especially how to write SQL with "with recursive"?
Thanks!
WITH RECURSIVE q AS
(
SELECT m
FROM mytable m
WHERE id = 'C'
UNION ALL
SELECT m
FROM q
JOIN mytable m
ON m.id = q.parent
)
SELECT (m).*
FROM q
WHERE (m).parent IS NULL
To implement recursive queries, you need a Common Table Expression (CTE).
This query computes ancestors of all parent nodes. Since we want just the top level, we select where level=0.
WITH RECURSIVE Ancestors AS
(
SELECT id, parent, 0 AS level FROM YourTable WHERE parent IS NULL
UNION ALL
SELECT child.id, child.parent, level+1 FROM YourTable child INNER JOIN
Ancestors p ON p.id=child.parent
)
SELECT * FROM Ancestors WHERE a.level=0 AND a.id=C
If you want to fetch all your data, then use an inner join on the id, e.g.
SELECT YourTable.* FROM Ancestors a WHERE a.level=0 AND a.id=C
INNER JOIN YourTable ON YourTable.id = a.id
Assuming a table named "organization" with properties id, name, and parent_organization_id, here is what worked for me to get a list that included top level and parent level org ID's for each level.
WITH RECURSIVE orgs AS (
SELECT
o.id as top_org_id
,null::bigint as parent_org_id
,o.id as org_id
,o.name
,0 AS relative_depth
FROM organization o
UNION
SELECT
allorgs.top_org_id
,childorg.parent_organization_id
,childorg.id
,childorg.name
,allorgs.relative_depth + 1
FROM organization childorg
INNER JOIN orgs allorgs ON allorgs.org_id = childorg.parent_organization_id
) SELECT
*
FROM
orgs order by 1,5;
tblUserProfile - I have a table which holds all the Profile Info (too many fields)
tblMonthlyProfiles - Another table which has just the ProfileID in it (the idea is that this table holds 2 profileids which sometimes become monthly profiles (on selection))
Now when I need to show monthly profiles, I simply do a select from this tblMonthlyProfiles and Join with tblUserProfile to get all valid info.
If there are no rows in tblMonthlyProfile, then monthly profile section is not displayed.
Now the requirement is to ALWAYS show Monthly Profiles. If there are no rows in monthlyProfiles, it should pick up 2 random profiles from tblUserProfile. If there is only one row in monthlyProfiles, it should pick up only one random row from tblUserProfile.
What is the best way to do all this in one single query ?
I thought something like this
select top 2 * from tblUserProfile P
LEFT OUTER JOIN tblMonthlyProfiles M
on M.profileid = P.profileid
ORder by NEWID()
But this always gives me 2 random rows from tblProfile. How can I solve this ?
Try something like this:
SELECT TOP 2 Field1, Field2, Field3, FinalOrder FROM
(
select top 2 Field1, Field2, Field3, FinalOrder, '1' As FinalOrder from tblUserProfile P JOIN tblMonthlyProfiles M on M.profileid = P.profileid
UNION
select top 2 Field1, Field2, Field3, FinalOrder, '2' AS FinalOrder from tblUserProfile P LEFT OUTER JOIN tblMonthlyProfiles M on M.profileid = P.profileid ORDER BY NEWID()
)
ORDER BY FinalOrder
The idea being to pick two monthly profiles (if that many exist) and then 2 random profiles (as you correctly did) and then UNION them. You'll have between 2 and 4 records at that point. Grab the top two. FinalOrder column is an easy way to make sure that you try and get the monthly's first.
If you have control of the table structure, you might save yourself some trouble by simply adding a boolean field IsMonthlyProfile to the UserProfile table. Then it's a single table query, order by IsBoolean, NewID()
In SQL 2000+ compliant syntax you could do something like:
Select ...
From (
Select TOP 2 ...
From tblUserProfile As UP
Where Not Exists( Select 1 From tblMonthlyProfile As MP1 )
Order By NewId()
) As RandomProfile
Union All
Select MP....
From tblUserProfile As UP
Join tblMonthlyProfile As MP
On MP.ProfileId = UP.ProfileId
Where ( Select Count(*) From tblMonthlyProfile As MP1 ) >= 1
Union All
Select ...
From (
Select TOP 1 ...
From tblUserProfile As UP
Where ( Select Count(*) From tblMonthlyProfile As MP1 ) = 1
Order By NewId()
) As RandomProfile
Using SQL 2005+ CTE you can do:
With
TwoRandomProfiles As
(
Select TOP 2 ..., ROW_NUMBER() OVER ( ORDER BY UP.ProfileID ) As Num
From tblUserProfile As UP
Order By NewId()
)
Select MP.Col1, ...
From tblUserProfile As UP
Join tblMonthlyProfile As MP
On MP.ProfileId = UP.ProfileId
Where ( Select Count(*) From tblMonthlyProfile As MP1 ) >= 1
Union All
Select ...
From TwoRandomProfiles
Where Not Exists( Select 1 From tblMonthlyProfile As MP1 )
Union All
Select ...
From TwoRandomProfiles
Where ( Select Count(*) From tblMonthlyProfile As MP1 ) = 1
And Num = 1
The CTE has the advantage of only querying for the random profiles once and the use of the ROW_NUMBER() column.
Obviously, in all the UNION statements the number and type of the columns must match.