ctesql server
My CTE runs in an infinite loop for a specific customer and I am not able to find out why.
Here is the query:
;WITH ClassTree
AS (SELECT ID, NAME, Parent_ID
FROM TableName
WHERE ID = 1
UNION ALL
SELECT T.ID, T.NAME, T.Parent_ID
FROM TableName T WITH (NOLOCK)
JOIN ClassTree
ON Parent_ID = ClassTree.ID
)
SELECT * FROM ClassTree
I found an answer for this!
1) Create a function that returns a table containing the desired dates
2) Do a cartesian product of the timeslots with the dates
3) Find the exceptions between the booked dates and the cartesian product
Edit: this is second attempt
Based on @Hannah Vernon's answer, here is a way to bypass the use of CTE inside an inline subquery, which is like self-joining the CTE and I presume is the reason for the poor efficiency. It uses analytic functions available only in the 2012 version of SQL-Server. Tested at SQL-Fiddle
This part can be skipped from reading, it's a copy-paste from Hannah's answer:
;With AccountHierarchy AS
(
SELECT
Root.AcctId AccountId
, Root.Name AccountName
, Root.ParentId ParentId
, 1 HierarchyLevel
, cast(Root.Acctid as varchar(4000)) IdHierarchyMatch
, cast(Root.Acctid as varchar(4000)) IdHierarchy
, cast(replace(Root.Name,'.','') as varchar(4000)) NameHierarchy
, cast(Root.Acctid as varchar(4000)) HierarchySort
, cast(Root.Name as varchar(4000)) HierarchyLabel ,
Root.CustomerCount CustomerCount
FROM
account Root
WHERE
Root.ParentID is null
UNION ALL
SELECT
Recurse.Acctid AccountId
, Recurse.Name AccountName
, Recurse.ParentId ParentId
, Root.HierarchyLevel + 1 HierarchyLevel
, CAST(CAST(Root.IdHierarchyMatch as varchar(40)) + '.'
+ cast(recurse.Acctid as varchar(40)) as varchar(4000)) IdHierarchyMatch
, cast(cast(recurse.Acctid as varchar(40)) + '.'
+ Root.IdHierarchy as varchar(4000)) IdHierarchy
, cast(replace(recurse.Name,'.','') + '.'
+ Root.NameHierarchy as varchar(4000)) NameHierarchy
, cast(Root.AccountName + '.'
+ Recurse.Name as varchar(4000)) HierarchySort
, cast(space(root.HierarchyLevel * 4)
+ Recurse.Name as varchar(4000)) HierarchyLabel
, Recurse.CustomerCount CustomerCount
FROM
account Recurse INNER JOIN
AccountHierarchy Root on Root.AccountId = Recurse.ParentId
)
Here we order the rows of the CTE using the IdHierarchyMatch and we calculate row numbers and a running total (from the next row up to the end.)
, cte1 AS
(
SELECT
h.AccountId
, h.AccountName
, h.ParentId
, h.HierarchyLevel
, h.IdHierarchy
, h.NameHierarchy
, h.HierarchyLabel
, parsename(h.IdHierarchy,1) Acct1Id
, parsename(h.NameHierarchy,1) Acct1Name
, parsename(h.IdHierarchy,2) Acct2Id
, parsename(h.NameHierarchy,2) Acct2Name
, parsename(h.IdHierarchy,3) Acct3Id
, parsename(h.NameHierarchy,3) Acct3Name
, parsename(h.IdHierarchy,4) Acct4Id
, parsename(h.NameHierarchy,4) Acct4Name
, h.CustomerCount
, h.HierarchySort
, h.IdHierarchyMatch
, Rn = ROW_NUMBER() OVER
(ORDER BY h.IdHierarchyMatch)
, RunningCustomerCount = COALESCE(
SUM(h.CustomerCount)
OVER
(ORDER BY h.IdHierarchyMatch
ROWS BETWEEN 1 FOLLOWING
AND UNBOUNDED FOLLOWING)
, 0)
FROM
AccountHierarchy AS h
)
Then we have one more intermediate CTE where we use the previous running totals and row numbers - basically to find where the end points for the branches of the tree structure:
, cte2 AS
(
SELECT
cte1.*
, rn3 = LAST_VALUE(Rn) OVER
(PARTITION BY Acct1Id, Acct2Id, Acct3Id
ORDER BY Acct4Id
ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING)
, rn2 = LAST_VALUE(Rn) OVER
(PARTITION BY Acct1Id, Acct2Id
ORDER BY Acct3Id, Acct4Id
ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING)
, rn1 = LAST_VALUE(Rn) OVER
(PARTITION BY Acct1Id
ORDER BY Acct2Id, Acct3Id, Acct4Id
ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING)
, rcc3 = LAST_VALUE(RunningCustomerCount) OVER
(PARTITION BY Acct1Id, Acct2Id, Acct3Id
ORDER BY Acct4Id
ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING)
, rcc2 = LAST_VALUE(RunningCustomerCount) OVER
(PARTITION BY Acct1Id, Acct2Id
ORDER BY Acct3Id, Acct4Id
ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING)
, rcc1 = LAST_VALUE(RunningCustomerCount) OVER
(PARTITION BY Acct1Id
ORDER BY Acct2Id, Acct3Id, Acct4Id
ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING)
FROM
cte1
)
and finally we build the last part:
SELECT
hier.AccountId
, hier.AccountName
--- -- columns skipped
, hier.CustomerCount
, TotalCustomerCount = hier.CustomerCount
+ hier.RunningCustomerCount
- ca.LastRunningCustomerCount
, hier.HierarchySort
, hier.IdHierarchyMatch
FROM
cte2 hier
OUTER APPLY
( SELECT LastRunningCustomerCount, Rn
FROM
( SELECT LastRunningCustomerCount
= RunningCustomerCount, Rn
FROM (SELECT NULL a) x WHERE 4 <= HierarchyLevel
UNION ALL
SELECT rcc3, Rn3
FROM (SELECT NULL a) x WHERE 3 <= HierarchyLevel
UNION ALL
SELECT rcc2, Rn2
FROM (SELECT NULL a) x WHERE 2 <= HierarchyLevel
UNION ALL
SELECT rcc1, Rn1
FROM (SELECT NULL a) x WHERE 1 <= HierarchyLevel
) x
ORDER BY Rn
OFFSET 0 ROWS
FETCH NEXT 1 ROWS ONLY
) ca
ORDER BY
hier.HierarchySort ;
And a simplification, using the same cte1 as the code above. Test at SQL-Fiddle-2. Please note that both solutions work under the assumption that you have a maximum of four levels in your tree:
SELECT
hier.AccountId
--- -- skipping rows
, hier.CustomerCount
, TotalCustomerCount = CustomerCount
+ RunningCustomerCount
- CASE HierarchyLevel
WHEN 4 THEN RunningCustomerCount
WHEN 3 THEN LAST_VALUE(RunningCustomerCount) OVER
(PARTITION BY Acct1Id, Acct2Id, Acct3Id
ORDER BY Acct4Id
ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING)
WHEN 2 THEN LAST_VALUE(RunningCustomerCount) OVER
(PARTITION BY Acct1Id, Acct2Id
ORDER BY Acct3Id, Acct4Id
ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING)
WHEN 1 THEN LAST_VALUE(RunningCustomerCount) OVER
(PARTITION BY Acct1Id
ORDER BY Acct2Id, Acct3Id, Acct4Id
ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING)
END
, hier.HierarchySort
, hier.IdHierarchyMatch
FROM cte1 AS hier
ORDER BY
hier.HierarchySort ;
A third approach, with only one CTE, for the recursive part and then only window aggregate functions (SUM() OVER (...)), so it should work in any version from 2005 upwards. Test at SQL-Fiddle-3 This solution assumes, like the previous ones, that there are 4 levels maximum in the hierarchy tree:
;WITH AccountHierarchy AS
(
SELECT
AccountId = Root.AcctId
, AccountName = Root.Name
, ParentId = Root.ParentId
, HierarchyLevel = 1
, HierarchySort = CAST(Root.Acctid AS VARCHAR(4000))
, HierarchyLabel = CAST(Root.Name AS VARCHAR(4000))
, Acct1Id = CAST(Root.Acctid AS VARCHAR(4000))
, Acct2Id = CAST(NULL AS VARCHAR(4000))
, Acct3Id = CAST(NULL AS VARCHAR(4000))
, Acct4Id = CAST(NULL AS VARCHAR(4000))
, Acct1Name = CAST(Root.Name AS VARCHAR(4000))
, Acct2Name = CAST(NULL AS VARCHAR(4000))
, Acct3Name = CAST(NULL AS VARCHAR(4000))
, Acct4Name = CAST(NULL AS VARCHAR(4000))
, CustomerCount = Root.CustomerCount
FROM
account AS Root
WHERE
Root.ParentID IS NULL
UNION ALL
SELECT
Recurse.Acctid
, Recurse.Name
, Recurse.ParentId
, Root.HierarchyLevel + 1
, CAST(Root.AccountName + '.'
+ Recurse.Name AS VARCHAR(4000))
, CAST(SPACE(Root.HierarchyLevel * 4)
+ Recurse.Name AS VARCHAR(4000))
, Root.Acct1Id
, CASE WHEN Root.HierarchyLevel = 1
THEN cast(Recurse.Acctid AS VARCHAR(4000))
ELSE Root.Acct2Id
END
, CASE WHEN Root.HierarchyLevel = 2
THEN CAST(Recurse.Acctid AS VARCHAR(4000))
ELSE Root.Acct3Id
END
, CASE WHEN Root.HierarchyLevel = 3
THEN CAST(Recurse.Acctid AS VARCHAR(4000))
ELSE Root.Acct4Id
END
, cast(Root.AccountName as varchar(4000))
, CASE WHEN Root.HierarchyLevel = 1
THEN CAST(Recurse.Name AS VARCHAR(4000))
ELSE Root.Acct2Name
END
, CASE WHEN Root.HierarchyLevel = 2
THEN CAST(Recurse.Name AS VARCHAR(4000))
ELSE Root.Acct3Name
END
, CASE WHEN Root.HierarchyLevel = 3
THEN CAST(Recurse.Name AS VARCHAR(4000))
ELSE Root.Acct4Name
END
, Recurse.CustomerCount
FROM
account AS Recurse INNER JOIN
AccountHierarchy AS Root ON Root.AccountId = Recurse.ParentId
)
SELECT
h.AccountId
, h.AccountName
, h.ParentId
, h.HierarchyLevel
, IdHierarchy =
CAST(COALESCE(h.Acct4Id+'.','')
+ COALESCE(h.Acct3Id+'.','')
+ COALESCE(h.Acct2Id+'.','')
+ h.Acct1Id AS VARCHAR(4000))
, NameHierarchy =
CAST(COALESCE(h.Acct4Name+'.','')
+ COALESCE(h.Acct3Name+'.','')
+ COALESCE(h.Acct2Name+'.','')
+ h.Acct1Name AS VARCHAR(4000))
, h.HierarchyLabel
, h.Acct1Id
, h.Acct1Name
, h.Acct2Id
, h.Acct2Name
, h.Acct3Id
, h.Acct3Name
, h.Acct4Id
, h.Acct4Name
, h.CustomerCount
, TotalCustomerCount =
CASE h.HierarchyLevel
WHEN 4 THEN h.CustomerCount
WHEN 3 THEN SUM(h.CustomerCount) OVER
(PARTITION BY h.Acct1Id, h.Acct2Id, h.Acct3Id)
WHEN 2 THEN SUM(h.CustomerCount) OVER
(PARTITION BY Acct1Id, h.Acct2Id)
WHEN 1 THEN SUM(h.CustomerCount) OVER
(PARTITION BY h.Acct1Id)
END
, h.HierarchySort
, IdHierarchyMatch =
CAST(h.Acct1Id
+ COALESCE('.'+h.Acct2Id,'')
+ COALESCE('.'+h.Acct3Id,'')
+ COALESCE('.'+h.Acct4Id,'') AS VARCHAR(4000))
FROM
AccountHierarchy AS h
ORDER BY
h.HierarchySort ;
A 4th approach, that calculates as an intermediate CTE, the closure table of the hierarchy. Test at SQL-Fiddle-4. The benefit is that for the sums calculations, there is no resctriction on the number of levels.
;WITH AccountHierarchy AS
(
-- skipping several line, identical to the 3rd approach above
)
, ClosureTable AS
(
SELECT
AccountId = Root.AcctId
, AncestorId = Root.AcctId
, CustomerCount = Root.CustomerCount
FROM
account AS Root
UNION ALL
SELECT
Recurse.Acctid
, Root.AncestorId
, Recurse.CustomerCount
FROM
account AS Recurse INNER JOIN
ClosureTable AS Root ON Root.AccountId = Recurse.ParentId
)
, ClosureGroup AS
(
SELECT
AccountId = AncestorId
, TotalCustomerCount = SUM(CustomerCount)
FROM
ClosureTable AS a
GROUP BY
AncestorId
)
SELECT
h.AccountId
, h.AccountName
, h.ParentId
, h.HierarchyLevel
, h.HierarchyLabel
, h.CustomerCount
, cg.TotalCustomerCount
, h.HierarchySort
FROM
AccountHierarchy AS h
JOIN
ClosureGroup AS cg
ON cg.AccountId = h.AccountId
ORDER BY
h.HierarchySort ;
Best Answer
I think this should find the problem record for you. It adds a
LEVELto your hierarchy, then looks for an individual ID record that exists at multiple levels.