Hi all,
Does JOIN order effect efficiency?
If I have three large tables to join together should I join the two that I know will cut the number of rows down a lot first and then join the 3rd table or does it make no difference (if I join the first and 3rd - which I know will be a large result set and then join the 2nd).
Thanks in advance,
Chiz.
How can I achieve the same effect as a cross join (since the merge operator doesn't have a cross join)?
Situation is this... a flat file has some header and footer information that I need to keep and attach to each row. So for simplicity sake of an example lets just say header has only 1 thing we care about - a row that says DATE=01/01/06.
I take the file and run a split to split into "Date" "Data" and "other" (other has all the throwaway rows in header and footer I don't care about). Then I use a derived column object to get all the columns out of the "Data". Finally I want to add that Date metadata back to every row in the data...
I thought this would be an easy thing to do.. but I can't seem to figure out how to duplicate that Date info into every row.. Hopefully I am overlooking something simple.
Thanks in advance.
i have been trying to determine which is the most efficient, with regards to speed and efficiency, between a view and a common/nested table expression when used in a join.
i have a query which could be represented as index view or a common table expression, which will then be used to join against another table.
the indexed view will use indexes when performing the join. is there a way to make the common table expression faster than an indexed view?
I have two select statements, in between select statement taking UNION ALL . I need to avoid the error
Warning: The join order has been enforced because a local join hint is used.
My question is fairly simple. When I join between two tables, I always use the ON syntax. For example:
SELECT
*
FROM
Users
JOIN UserRoles
ON (Users.UserRoleId = UserRoles.UserRoleId)
No problems there. However, if I then decide to further filter the selection based on some trait of the UserRole, I have two options: I can add the condition as a WHERE statement, or I can add the condition within the ON block.
--Version 1:
SELECT
*
FROM
Users
JOIN UserRoles
ON (Users.UserRoleId = UserRoles.UserRoleId)
WHERE
UserRoles.Active = 'TRUE'
-- Version 2
SELECT
*
FROM
Users
JOIN UserRoles
ON (Users.UserRoleId = UserRoles.UserRoleId
AND UserRoles.Active = 'TRUE')
So, the question is, which is faster/better, if either? The Query Analyzer shows the two queries have the exact same execution plan, which makes sense, since they're both joining the same tables. However, I'm wondering if adding the condition in the ON statement results in fewer rows the JOIN statement initially needs to join up, thus reducing the overall initial size of the results table before the WHERE conditions are applied.
So is there a difference, performance wise? I imagine that if Users had a thousand records, and UserRoles had 10 records, then the JOIN would create a cartesian product of the two tables, resulting in 10,000 records in the table before the WHERE conditions are applied. However, if only three of the UserRoles is set to Active, would that mean that the resulting table, before applying WHERE conditions, would only contain 3000 records?
Thanks for whatever information you can provide.
Hi,
Here is my code:
ALTER PROCEDURE dbo.sp_GetPeopleDetails_1
@OrderByClause varchar(100)
AS
DECLARE @SQLStatement varchar(255)
SELECT @SQLStatement = 'SELECT People.PeopleID, People.FirstLastName, People.Title,
Departments.AcademicArea, Shifts.ShiftName, People.TShirt,
People.Parking
FROM Departments INNER JOIN
People ON
Departments.DepartmentID = People.DepartmentID
INNER JOIN
Shifts ON People.ShiftID = Shifts.ShiftID
order By ' +
@OrderByClause
EXEC(@SQLStatement)
/* SET NOCOUNT ON */
RETURN
When I run it, the error is: "Incorrect syntax near the keyword 'IN'."
Can anyone point my mistake?
Thanks.
like so often my Forums database design (in its simplest form) is:Forums -ForumID -Title -CategoryForumsMsgs -fmID -DateIn -AuthorID -MessageI need to create a sql query which returns all forum titles along with some data for 1) the first message entry (date created and author) and 2) the last one. So how can I do a JOIN query which joins with a ORDER BY clause so that the top/bottom entry only is joined from the messages table?
View 2 Replies View RelatedHi, I am writing a small search engine.
There are two tables. The first one holds the search engine main index, the second one is link table.
I have the following query that retrieves results. I would like to sort the results by:
dbo.OCCURS2(LOWER(:query),se_links.anchor). se_links.anchor obviously comes from se_links table, so I get an error. Is it possible to done in one query?
I'm using MSSQL 2005. Thanks.
PS. Function OCCURS2 returns number of occurrences of one string in other.
Code:
select
id as Id,
uri as ElementUri,
size as Size,
modified_date as ModifiedDate,
title as Title,
text as Text,
dbo.OCCURS2(LOWER(:query),Title) as TitleOcc,
dbo.OCCURS2(LOWER(:query),Text) as BodyOcc
FROM se_index
WHERE (title LIKE :query) OR
(text LIKE :query) OR
(id IN
(SELECT se_links.target_index_id
FROM se_links INNER JOIN
se_index AS se_index_1 ON
se_links.target_index_id = se_index_1.id AND
se_links.anchor LIKE :query))
Trying to understand complex joins (or complex to me, at least).I have a series of tables which have data I want to join in order to get a useful report. Most of the joins work fine, e.g.:
SELECT DISTINCT *
From Documents INNER JOIN LookUpTable
ON LookUpTable.ObjectId = Documents.LastVersionOwnerId
This give me the name of the person who owns the most recent version of a document, as the LookUpTable table maps userid numbers to names.But I also want to correlate the OriginalOwnerId column from the same Document table with its LookUpTable counterpart. I can't figure out how to get that second join, for the same tables, to work.
I have an problem with the order of the results after a join.
My first query works fine and the order of field Name ist correct.
Select *
FROM
(SELECT * FROM
dtree A1
WHERE
A1.Subtype=31356
AND
A1.DataID IN
(select DataID from dtreeancestors where AncestorID=9940974)) t
When I do a join the order of the left table changes
Select *
FROM
(SELECT * FROM
dtree A1
WHERE
A1.Subtype=31356
AND
A1.DataID IN
(select DataID from dtreeancestors where AncestorID=9940974)) t, llattrdata A4
WHERE
t.DataID = A4.ID
How can I do a join and keep the order of the left table?
Hi all,
I faced a problem, I have two tables - part and partmaster
part : part_no, part_qty (no key)
partmaster : part_no, part_description (primary key : part_no )
I want to select table part.* and partmaster.part_description.
(run on mssql 2k)
select a.*, b.part_description
from part a, partmaster b where a.part_no *= b.part_no
I want to and expect to have the result order like table "part". However, after the join, the order is different. I try to run it on mssql 7.0, the order is ok.
Then I modify and run the statement select a.* from part a, partmaster b where a.part_no *= b.part_no on 2k again. The result order is ok.
can anyone tell me the reason?
Now I try to fix this problem is adding a sequence field "part_seq" into table "part" and run the statement by adding a order by part_seq.
It does work!
Regards,
Simon
In Outer join, I would like to add the outer columns that don't exist in the right table for each order number. So currently the columns that don't exist in the right table only appear once for the entire set. How can I go about adding PCity, PState to each order group, so that PCity and PState would be added as null rows to each group of orders?
if OBJECT_ID('tempdb..#left_table') is not null
drop table #left_table;
if OBJECT_ID('tempdb..#right_table') is not null
drop table #right_table;
create table #left_table
[Code]....
I have a sqlserve, which service account is 'local system', running in machine A.
A credential ,which associated a windows user U1 in machine A, mapped to a sqlserver login Login1.
A file named 1.txt that only can be accessed by U1 in machine A.
A CLR procedure P1 that would read the 1.txt file.
I encounter a error when i access the 1.txt file through P1 as Login1:
A .NET Framework error occurred during execution of user-defined routine or aggregate "HelloWorld":
System.UnauthorizedAccessException: Access to the path 'E:1.txt' is denied.
System.UnauthorizedAccessException:
at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)
at System.IO.FileStream.Init(String path, FileMode mode, FileAccess access, Int32 rights, Boolean useRights, FileShare share, Int32 bufferSize, FileOptions options, SECURITY_ATTRIBUTES secAttrs, String msgPath, Boolean bFromProxy)
at System.IO.FileStream..ctor(String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize, FileOptions options)
at System.IO.StreamReader..ctor(String path, Encoding encoding, Boolean detectEncodingFromByteOrderMarks, Int32 bufferSize)
at System.IO.StreamReader..ctor(String path)
at StoredProcedures.StoredProcedure1(SqlString fileName)
.
I think it need a credential when a sqlserver login access some resource outside the sqlserver, so i add a credential and mapped to the login
any suggestions would be appreciated.
And please correct me if i have any inaccurate concept.
I have this stored procedure. I want to run a few simple SQL functions against my tables. In particular I want to take a subset of records (One or Two years worth) and calculate AVG, VAR and STDEV.
It does not work the way I thought it would. I end up with the whole input table in #tempor1 which is about 6 years worth of records.
set ANSI_NULLS ON
set QUOTED_IDENTIFIER OFF
GO
ALTER PROCEDURE [dbo].[findAve1YearDailyClose_MSFT]
AS
BEGIN
SET NOCOUNT ON;
SELECT adjClosed, volume INTO #tempor1 FROM dbo.dailyCl_MSFT
GROUP BY dateTimed, adjClosed, volume
HAVING (dateTimed > DATEADD (year, -1, MAX (dateTimed)))
SELECT AVG (adjClosed) AS "AVGAdjClose1Year",
VAR (adjClosed) AS "VARAdjClose1Year", AVG (volume) AS "AVGVolume1Year",
STDEV (volume) AS "STDEVVolume1Year", COUNT (*) AS "total"
FROM #tempor1
END
Thus if I change the number of years I subtract from the latest date from 1 to 2 I end up with the same result. What is the problem?
Thanks.
I want to select one field from a table,but it should on some conditionswhich refer to 5 table ,such as A.FILED1=B.FIELD1 AND B.FIELD2=C.FIELD3 AND....Should I use case "select sum(a.amount) from a,b,c,... wherea.field1=b.field1 and b.field2=c.field2 and ..." or "select sum(a.amount)from select b.field1 from select c.field2 from...."?And which case is moreefficiency?thanks!我想计算一个表中的某个字段的和，但此记录需在从多个 表中查询此记录是否满足特定的条件。那么我是用select ..from ...where ..and ..and..and ..and ..还是用select ..fromselect ..from select ..from ......？请问是哪一个效率高？谢谢！
View 2 Replies View RelatedWhen running a trace on a database, how does if affect that databases performance? Does it slow it down at all?
Thanks In Advance,
Chris
Hello,
What happens to these REPLication agents if SQL Agent is stopped and started:
Snapshot Agents
Merge Agents
Misc Maintenance Agents
Can the agent be stopped and started with no thought to the status of replication, or should the replication state be modified in some way before any change to the status of the Agent?
(I know REPL depends on agent, so wuestion is, can REPL simply resume or not when agent is re-started.)
Thanks.
MichaelGG
If the server is upgraded to Windows 2000, will SQL 6.5 require to be upgraded to SQL 7 or 2000?
View 1 Replies View RelatedDoes someone know if doing a reindex on a clustered or non-clustered index cause the snapshot file to grow? In other words, is the data that makes up the snapshot copied from the source to the snapshot database? If a normal reindex is done on the underlying database, will it block users from acessing the snapshot? Any help would be appreciated.
View 1 Replies View RelatedHi..
I want to know that when I do something like..
Select Query
Left Join
Select Query 2
Left Join
Select Query 3
How does it work actually?
As in, whether Query 2 & Query 3 will work only on the records retrieved by Query 1 only.
Or, all the select statements retrieves all the records and then the condition is applied to filter out the results.
Also, does the order of the Select statements make any difference on the speed?
Thanks
Hello,I am looking at optimizing site searching on a web application. I have two thoughts on the idea:1. create views with fulltext indexes combining records from multiple tables.2. create a table with an xml column and primary index. I understand the xml column type has the overhead of a BLOB under the hood, but that a primary xml index can "shred" the contents and improve parsing. I also read the xml column is actually searched as a tree, providing some variant of log(n) run time. Does anyone know of good literate on this subject, the more big O notation, runtime analysis types of posts the better.Thanks
View 5 Replies View RelatedHi guys,
Since the project that i'm developing is rapidly increasing, the pages seems to be getting slower everytime you view it. I would like to ask if code below would be efficient enough for several simultaneous request of data or if you have any other suggestions, you are welcome to add:
1 Public Shared Function QueryDatabase(ByVal sql As String) As DataTable2 3 ' SQL Server Connection Object Variable4 Dim _oConnection As SqlConnection5 ' SQL Server Command Object Variable6 Dim _oCommand As SqlCommand7 ' SQL Server Data Adapter Object Variable8 Dim _oAdapter As SqlDataAdapter9 ' DataTable Object Variable (Early Binding)10 Dim _oDataTable As New DataTable11 12 ' Instantiate Connection Object with connection string13 _oConnection = New SqlConnection("Data Source=XXX.XXX.XXX.XXX;Initial Catalog=XXXXXX;User=XXX;Pwd=XXX;")14 ' Instantiate Command Object with SQL String and Connection Object15 _oCommand = New SqlCommand(sql, _oConnection)16 ' Instantiate Data Adapter Object with Command Object17 _oAdapter = New SqlDataAdapter(_oCommand)18 ' Fill the DataTable Object with the retrieve records19 _oAdapter.Fill(_oDataTable)20 21 ' Release resources used by DataAdapter Object22 _oAdapter.Dispose()23 24 ' Release resources used by Command Object25 _oCommand.Dispose()26 27 ' Close the connection of the Connection Object from SQL Server28 _oConnection.Close()29 30 ' Release resources used by Connection Object31 _oConnection.Dispose()32 33 ' Return the retrieve records34 Return _oDataTable35 36 End Function Thanks a lot.
Hey,I am developing a website which will be used by a large number of people so I am concerned about efficiency.Sorry for the three posts but anyone with any info would be appreciated.The database has the following tables: FACILITY-----MEETING ---- | | USERS---- -------- MEETING_INVITE -------- REMINDER | | ---------CONTACTS-------When the user logs in I use there username to access the rest of the tables. I get all of the users information out of the database in one go and store it in a dataset.So when a user accesses there meetings page, I pass the dataset to that page with a server transfer.Question 1 > Is it more efficient to open the database once and access all the information and pass the information to seperate tables or is it more efficient to access the database on the individual pages and thus not passing of information.---------------------------------------------------------------------------------------------------------------In order to access the information I use 6 Select statements in a rowHere is an example of my select statments: SELECT * FROM USERS WHERE email = textbox_emailSELECT FACILITY.* FROM FACILITY, USERS WHERE FACILITY.email = USERS.email AND USERS.email = textbox_emailBy the time I get to the REMINDER table I am combining all the tables and my query is eight lines long.Question 2 > Is there a way of combining the results of a previous select to access information?---------------------------------------------------------------------------------------------------------------Question 3 > What do you think of my table design? The lines represent one to many relationships. If you can give me any tips on databases please do.Thanks for your time,Padraic
View 2 Replies View RelatedHello all,I am developing a website which may be used by a large number of people in the future and I am concerned about performance.
Is it better to have one table with 50, 000 rows or 5,000 tables with 10 rows each?
Is there a way to divide a table in two if the table reaches a certain size?
Is there a limit on the size of tables?
Is there a limit on the number of tables?
Is it possible to create tables from vb.net?
Is it possible to program checks into sql server? For example, could I delete data that has passed a certain date or send an automated email when a time is reached?
Thanks for your time,Padraic
Hey people
I'd be really grateful if someone can help me with this. Could someone explain the following:
If the following code is executed, it runs instantly:
declare @SellItemID numeric (8,0)
select @SellItemID = 5296979
SELECT distinct s.sell_itm_id
FROM stor_sell_itm s
WHERE (s.sell_itm_id = @SellItemID )
However, if I use this WHERE clause instead -
WHERE (@SellItemID = 0 OR s.sell_itm_id = @SellItemID)
- it takes 70 micro seconds. When I join a few more tables into the statement, the difference is 4 seconds!
This is an example of a technique I'm using in loads of places - I only want the statement to return all records if the filter is zero, otherwise the matching record only. I think that by using checking the value of the variable in the WHERE clause, a table scan is used instead of an index. This seems nonsensical since the variable is effectively a constant. Wrapping the entire select statement with an IF or CASE works, but when I've got 10 filters I'd have to 100 select statements.
I DON'T GET IT!! There must be a simple answer, HELP!!
Jo
PS this problem seems to occur both in 6.5 and 7.0
Hi All,
I tried my luck in the Access forum and I've search the web and MSDN for an answer with little luck.
Simply, is it better to update a table via an UPDATE query or Recordset manipulation?
I have read that if you were to update 10,000 records an UPDATE query is more efficient (obviously), but does that transend down to say 1 - 10 updates?
i.e. There are six unique updates I want to make to 6 different rows. Should I code the backend VB to execute 6 different queries or seek and update a recordset?
It's a MS Access XP app with ADO 2.8.
My gut feeling on this is that making 6 update queries is more efficient, both with system resources and record-locking issues; I'd just like another opinion on the matter.
I appreciate your help!
Thanks,
Warren
I am using nested cursors in my script below, and wonder if there is a more efficient way please?
USE ar
GO
DECLARE @mortgage INT,
@mortgage_sequence int,
@getMortgage CURSOR,
@notes_1 varchar(MAX),
@notes_2 varchar(MAX),
@notes_3 varchar(MAX),
@notes_4 varchar(MAX),
@notes_5 varchar(MAX),
@notes_6 varchar(MAX),
@notes_7 varchar(MAX),
@notes_8 varchar(MAX),
@notes_9 varchar(MAX),
@notes_10 varchar(MAX),
@notes_11 varchar(MAX),
@notes_12 varchar(MAX),
@notesComplete varchar(MAX),
@addedUser varchar(255),
@addedDate varchar(255),
@amendedUser varchar(255),
@amendedDate varchar(255),
@sequence int,
@getDetail CURSOR
SET @getMortgage = CURSOR FOR
SELECT DISTINCT Mortgage_Number, Mortgage_Note_Sequence_No
FROM format_additional_notes
GROUP BY Mortgage_Number, Mortgage_Note_Sequence_No
ORDER BY Mortgage_Number ASC
OPEN @getMortgage
FETCH NEXT
FROM @getMortgage INTO @mortgage, @mortgage_sequence
WHILE @@FETCH_STATUS = 0
BEGIN
SET @getDetail = CURSOR FOR
SELECT ltrim(rtrim(Additional_Text_1)),
ltrim(rtrim(Additional_Text_2)),
ltrim(rtrim(Additional_Text_3)),
ltrim(rtrim(Additional_Text_4)),
ltrim(rtrim(Additional_Text_5)),
ltrim(rtrim(Additional_Text_6)),
ltrim(rtrim(Additional_Text_7)),
ltrim(rtrim(Additional_Text_8)),
ltrim(rtrim(Additional_Text_9)),
ltrim(rtrim(Additional_Text_10)),
ltrim(rtrim(Additional_Text_11)),
ltrim(rtrim(Additional_Text_12)),
Mortgage_Note_Sequence_No,
Extra_Added_by_User,
Extra_Added_on_Date,
Extra_Amended_By_User,
Extra_Amended_By_Date
FROM format_additional_notes
WHERE Mortgage_Number = @mortgage AND Mortgage_Note_Sequence_No = @mortgage_sequence
ORDER BY Mortgage_Note_Sequence_No
OPEN @getDetail
SET @notesComplete = ''
FETCH NEXT FROM @getDetail INTO @notes_1,
@notes_2,
@notes_3,
@notes_4,
@notes_5,
@notes_6,
@notes_7,
@notes_8,
@notes_9,
@notes_10,
@notes_11,
@notes_12,
@sequence,
@addedUser,
@addedDate,
@amendedUser,
@AmendedDate
WHILE (@@FETCH_STATUS = 0)
BEGIN
SET @notesComplete = @notesComplete +
ISNULL(@notes_1,'') + ' ' +
ISNULL(@notes_2,'') + ' ' +
ISNULL(@notes_3,'') + ' ' +
ISNULL(@notes_4,'') + ' ' +
ISNULL(@notes_5,'') + ' ' +
ISNULL(@notes_6,'') + ' ' +
ISNULL(@notes_7,'') + ' ' +
ISNULL(@notes_8,'') + ' ' +
ISNULL(@notes_9,'') + ' ' +
ISNULL(@notes_10,'') + ' ' +
ISNULL(@notes_11,'') + ' ' +
ISNULL(@notes_12,'')
FETCH NEXT FROM @getDetail INTO @notes_1,
@notes_2,
@notes_3,
@notes_4,
@notes_5,
@notes_6,
@notes_7,
@notes_8,
@notes_9,
@notes_10,
@notes_11,
@notes_12,
@sequence,
@addedUser,
@addedDate,
@amendedUser,
@AmendedDate
END
INSERT INTO format_additional_notes_1
(Mortgage_Number,
Mortgage_Note_Sequence_No,
Additional_Text,
Extra_Added_By_User,
Extra_Added_on_Date,
Extra_Amended_By_User,
Extra_Amended_By_Date)
VALUES
( @mortgage,
@sequence,
@notesComplete,
@addedUser,
@addedDate,
@amendedUser,
@amendedDate)
CLOSE @getDetail
DEALLOCATE @getDetail
FETCH NEXT
FROM @getMortgage INTO @mortgage, @mortgage_sequence
END
CLOSE @getMortgage
DEALLOCATE @getMortgage
GO
I would like to use MVJ's formula for creating a date table.
I would like to use it with our main ERP database. However, I am reluctant to make changes to it because I fear that at some point when we upgrade that software and it's database that the upgrade program will delete my table.
So, here is my question. Performance wise, does it matter whether I add the date table to our ERP database or if I create another database (on the same server) for the custom date table? Does linking between databases take substantially longer than linking within the same database?
Hi,
okay so I'm refactoring some code at the moment. At the moment, I'm working on a search screen. This search screen lets the user enter a number of criterias, I'm working on drags data from a view and then programmatically filters it according to the search filters.
This is obviously inefficent and non-scalable as the view drags out every entry and returns to the data layer, which then filters it.
I'm wondering what the best way to refactor this? i'm thinking the best way is to tell the db what to filter on, so it'll only drag out the right amount of data.
Therefore, should I keep the view? Is there any way of entering parameters into views or am i going to need to change this into a stored proc?
hi,Allcould you tell me which case is more efficiency?(my tables have no index)And does it has any else case more efficiency?case1:"select sum(Invoice_Production.Quantity) from Invoice_Production,(select[dat_Item].ItemCode from [dat_Item],(select [dat_MachineType].MachineTypeIDfrom [dat_MachineType]"&subQuery&") as T3 where [dat_Item].MachineTypeID =T3.machinetypeid) as T1,(select [Invoice].InvoiceNo from Invoice,(select[users].user_id from [users] where [Users].User_ID = '"& rs2(0) &"') as T4where T4.User_ID = invoice.dealerno and Invoice.Cyear >= "&startYear&" andInvoice.Cyear <= "&endYear&" and Invoice.Cmonth >= "&startMonth&" andInvoice.Cmonth <= "&endMonth&") as T2 where invoice_production.ItemCode =T1.ItemCode and T2.invoiceno = invoice_production.invoiceno"case2:"select sum(Invoice_Production.Quantity) from[Invoice_Production],[Invoice],[dat_MachineType],[dat_Item],[users] where[users].user_id = [invoice].DealerNo and [dat_Item].ItemCode =[Invoice_Production].ItemCode and [dat_Item].MachineTypeID =[dat_MachineType].MachineTypeID and [Invoice_Production].InvoiceNo =[Invoice].InvoiceNo and [Users].User_ID = '"& rs2(0) &"' and Invoice.Cyear
Quote:
How efficient is ti to use join views in a database?I'm developing an e-commerce system and using join views to join theproduct, product category and product review tables and wondering if thiswould have any adverse effect on performance.Thanks in advance
View 3 Replies View RelatedI have the following 2 tables:location:placelftrgt-------------------Europe099England110France1120Italy2130Asia100199London1212staff:namelocLft--------------Edwards0Smith1Leveil11Rossi21Lee12Chan100location uses the Celko hierarchy model.I wish to retrieve for a location the names of all staff within it andthe hierarchy of place associated with that member of staff, eg aquery for Europe should return all staff in Europe, and for Lee I wishto return Lee-London, Lee-England, Lee-Europe etc.I can achieve this using a subquery, ieSELECT name, placeFROM staff, locationWHERE name IN (SELECT nameFROM staff, locationWHERE place='Europe' And locLft>=location.lft AndlocLft<=location.rgt)AND locLft>=lft AND locLft<=rgtBut is this the most efficient way of doing so?Thanks
View 1 Replies View Related
Greetings all,
I need to determine a hierarchy from a table with EmpID's and SupID's. Basically, the President doesn't have a SupID so it will be null. I need to determine programatically the hierarchy to keep it simple.
I have code that works and I was hoping for advice on optimizing it 'cuz it uses a cursor.
Also, It only deals with less than 300 records.
Code Block
CREATE TABLE Employee(fName varchar(30), EmpID int, SupID int)
INSERT INTO Employee SELECT 'Adam', 1, 4
INSERT INTO Employee SELECT 'Joe', 2, 4
INSERT INTO Employee SELECT 'John', 3, 4
INSERT INTO Employee SELECT 'Frank', 4, 10
INSERT INTO Employee SELECT 'Jane', 5, 10
INSERT INTO Employee SELECT 'Kristy', 6, 10
INSERT INTO Employee SELECT 'Angie', 10, 11
INSERT INTO Employee SELECT 'Ron', 11, NULL
--=====================================================================================
-- CODE
--=====================================================================================
CREATE TABLE #temp(Hierarchy int, myName varchar(30), SupID int, EmpID int)
INSERT INTO #temp SELECT 1, fName, SupID, EmpID FROM Employee WHERE SupID IS NULL
--NULL SupID means that they are at the top most branch
DECLARE @Counter int --Counter is used to increment
SET @Counter = 1
DECLARE MY_CURSOR Cursor
FOR
SELECT SupID, EmpID, fName
FROM Employee
ORDER BY SupID --ORDER BY SupID to bring NULLs to top
Open My_Cursor
DECLARE @EmpID int, @SupID int, @Name varchar(30)
FETCH NEXT FROM MY_Cursor INTO @EmpID, @SupID, @Name
WHILE (@@FETCH_STATUS = 0)
BEGIN
SET @Counter = (SELECT MAX(Hierarchy) FROM #temp) + 1 --Get the highest hierarchy ID and increment by 1
INSERT INTO #temp
SELECT @Counter, fName, SupID, EmpID
FROM Employee
WHERE SupID IN (SELECT EmpID FROM #temp WHERE EmpID = @SupID)
FETCH NEXT FROM MY_CURSOR INTO @EmpID, @SupID, @Name
END
CLOSE MY_CURSOR
DEALLOCATE MY_CURSOR
SELECT * FROM #temp
DROP TABLE #temp
Thanks in advance,
Adam