Explicit Transactions
Feb 27, 2006
I have an cursor that loops 720 times.
Each FETCH does 6 INSERTS.
Each FETCH the 6 INSERTs a total of 200-300 records appended.
Would explicit transactions speed up the cursor?
In Oracle, I would keep track of how many times I've looped, and commit every nth time. I would put a catch remainder COMMIT at the end of the procedure.
I've got the IF @@TRANCOUNT > 19 COMMIT TRAN (about 6k records), but say I had <= 19 remaining at the end of the cursor, how do you get those to commit? I tried to put an IF @@TRANCOUNT > 1 COMMIT TRAN, but that didn't work.
What's a good @@TRANCOUNT to commit at in this case?
Thanks crew,
Carl
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Jun 21, 2006
I€™m using triggers for some more advanced integrity check. The problems is that the same trigger can be run from explicit transaction (this is when I start transaction from .NET) and as autocommit transaction ( very rare, only when we do some maintenance directly with SQL statements).
Currently if I want to rollback transaction from trigger I only issue RAISERROR statements, then .NET application catches this error and generates rollback. But the problem is if trigger is raised from some SQL statements outside .NET application (normally some maintenance work direct from SQL manager ) in that case error is generated but there is no rollback.
Is there any way to distinguish if transaction in trigger is explicit or autocommited, because for autocommited transaction I also need use ROLLBACK TRANSACTION?
I€™m using SQL 2005!
Best regards
edvin
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Jul 23, 2005
When I need to perform an update against multi-million row table Itypically specify @@rowcount, to reduce locks.e.g.set @@rowcount 1000while exists (select * from myTable where col2 is null)update myTableset col2 = col1 + 'blahblah'where col2 is nullHowever, my boss' script does something like this. I think it works OKbut it seems overly complicated to me. Any thoughts?while exists (....)begin traninsert into #tableselect ...update myTableset ...from myTable join #table ...(@numberOfRows is a counter variable, tracking #rows that have beenupdated since last batch)if @numberOfRows > 1000begincommitbegin tranendend
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May 22, 2005
Hi there,
I have decided to move all my transaction handling from asp.net to stored procedures in a SQL Server 2000 database. I know the database is capable of rolling back the transactions just like myTransaction.Rollback() in asp.net. But what about exceptions? In asp.net, I am used to doing the following:
<code>Try 'execute commands myTransaction.Commit()Catch ex As Exception Response.Write(ex.Message) myTransaction.Rollback()End Try</code>Will the database inform me of any exceptions (and their messages)? Do I need to put anything explicit in my stored procedure other than rollback transaction?
Any help is greatly appreciated
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Feb 4, 2008
is anybody using this? it looks like a lot of trouble to return a formatted string. I am considering it for something. Any opinions?
http://technet.microsoft.com/en-us/library/aa226532(SQL.80).aspx
caution: you have to X out of the Do You Want to Download Silverlight popup.
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Jul 23, 2005
i have a situation, where i need to group my information by a certainid, but that information which should already be grouped, i need toorder based on a number in one of the columnsexample:<ex id=2 listorder=1><description>desc 2</description></ex><ex id=1 listorder=2><description>desc 1</description></ex>in my order clause i first put order by the id, and it will group theinformation accordingly, but will put the lowest number id first, notcaring about the listorderbut if i order by the listorder column first, the information isn'tgroupd properlyi don't know if i made myself clear enough?hope someboyd can help methnx in advance
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Jun 8, 1999
Hi ,
I've tried to switch MS-Sql/Server 6.5 on explicit_transactions
without success.
(set implicit_transaction on/off)
What is the exact syntax for doing that ?
Herve
(PS: Thanks Gregory for your quick answer )
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Jun 3, 1999
Hi All,
I don't know MS-SQLserver internal system at all. I 've just used Oracle
a couple years ago and so in some cases (e.g using TP-monitor MTS or Tuxedo)
you can switch off the implicit transaction by using
the option AUTOCOMMIT ON/OFF.
How can switch off the implicit transaction system on MS-SQLServer ?
In advance thanks,
Herve
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Sep 7, 2004
I created a SELECT statement that uses the FOR XML EXPLICIT clause so that SQL Server data can be exported to another system. Format thios system accepts is XML. What should I define within a DTS package so that this Select statement is executed and an XML file is created?
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Jan 30, 2007
Hello,
In the SP below, I get the following error when I run it:
Explicit value must be specified for identity column in table 'Tests' when IDENTITY_INSERT is set to ON.
From what I've read of the INSERT method, it says you can add a variable value. So I don;t understand why it won't take mine.
CREATE PROC qaspAddTestRecord AS
DECLARE @aKey bigint
DECLARE @aTestSuiteId bigint
exec qaspGetNewID 'Tests', @aKey OUT
SELECT @aTestSuiteId= NewID FROM ID WHERE TableName='TestSuite'
SET IDENTITY_INSERT Tests ON
INSERT INTO Tests (TestSuiteId, TestIDInternal) VALUES (@aTestSuiteId, @aKey)
SET IDENTITY_INSERT Tests OFF
GO
--PhB
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Jan 7, 2008
Hello all,I'm trying to generate some XML directly from MS SQL with thefollowing codeSELECT1 AS tag, NULL AS parent, NULL AS [GoogleCustomizations!1], NULL AS [Annotations!2], NULL AS [Annotation!3], NULL AS [Annotation!3!about], NULL AS [Annotation!3!score], NULL AS [Label!4], NULL AS [Label!4!name]UNIONSELECT2 AS tag, 1 AS parent, NULL, NULL, NULL, NULL, NULL, NULL, NULLUNIONSELECTTOP 503 AS tag, 2 AS parent, NULL, NULL, NULL, 'www.' + domainName, 1 -- score, NULL, NULLFROM tbl_auDomainNameUNIONSELECT4 AS tag, 3 AS parent, NULL, NULL, NULL, NULL, NULL, NULL, '_cse_ad-o6lgdody'FOR XML EXPLICITThe XML it needs to create is as following<GoogleCustomizations><Annotations><Annotation about="www.clickfind.com.au/*" score="1"><Label name="_cse_ad-o6lgdody" /></Annotation><Annotation about="www.lookle.com/*" score="1"><Label name="_cse_ad-o6lgdody" /></Annotation><Annotation about="www.sensis.com.au/*" score="1"><Label name="_cse_ad-o6lgdody" /></Annotation></Annotations></GoogleCustomizations>It is currently creating<GoogleCustomizations><Annotations><Annotation about="www.10000steps.org.au" score="1" /><Annotation about="www.101fm.asn.au" score="1" /><Annotation about="www.aao.gov.au" score="1"><Label name="_cse_ad-o6lgdody" /></Annotation></Annotations></GoogleCustomizations>I cannot get my head around how I can get the label <Labelname="_cse_ad-o6lgdody" />in each element. Does anyone know?Thanks in advance.
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Jan 31, 2007
HiI have to create an XML file based on a SQL SERVER 2005 table.Everything works fine:SELECT 1 as Tag,
NULL as Parent,
Ex_Id as [Exam!1!Ex_Id],
NULL as [Ex_Title!2!!cdata]
FROM Exams
WHERE ex_State = 'P'
UNION ALL
SELECT 2 as Tag,
1 as Parent,
Ex_Id,
ex_Title
FROM Exams
WHERE ex_State = 'P'
order by [Exam!1!Ex_Id], [Ex_Title!2!!cdata]
FOR XML EXPLICIT, ROOT('Exams')
BUT when i add another column, a text column, I get into trouble: SELECT 1 as Tag,
NULL as Parent,
Ex_Id as [Exam!1!Ex_Id],
NULL as [Ex_Title!2!!cdata],
NULL as [Ex_Situation!3!!cdata]
FROM Exams
WHERE ex_State = 'P'
UNION ALL
SELECT 2 as Tag,
1 as Parent,
Ex_Id,
ex_Title,
ex_Situation
FROM Exams
WHERE ex_State = 'P'
order by [Exam!1!Ex_Id], [Ex_Title!2!!cdata], [Ex_Situation!3!!cdata]
FOR XML EXPLICIT, ROOT('Exams')
The problem is clearly the fact that i have to sort on the text column, plus the fact that this column requires the CDATA tag enclosurePlease help me....i'm desperate :(
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Jan 19, 2004
Hi:
How can I force MsSQL to a explicit DateFormat.
Like: 'DD/YY'
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May 20, 2008
performance wise what is the difference between following queries
Select * from A, B Where A.ID = B.ID
Select * from A INNER JOIN B ON A.ID = B.ID
(ID is the primary key)
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Apr 24, 2006
I am developing an integration process between two databases. One ofthem is a SQL Server 2000 and the other is using MSDE 2000. Theintegration process is done in C# (VS2003).The main database is the SQL Server, the MSDE will contain a reallysmall subset of the data found on the main. To help diminish the amountof time taken to develop an integration process between thosedatabases, the same structure are found on both side. The onlydifference, when I insert data in the MSDE from the SQL Server, I setthe IDENTITY_INSERT to ON and use the same IDs found on the SQL Server.I can insert one set of data without problem, but from there, if I tryagain, I will always receive the "Cannot insert explicit value foridentity column in table ... when IDENTITY_INSERT is set to OFF." Isaw on Microsoft website the article ID 878501; I noticed I was usingMSDE sp3, I upgraded to SP4... and I still have the problem.I know, when I call the update function on the sqldataadapter, theadapters contain the IDENTITY_INSERT ON and it's set to OFF after theinsert. The "Cannot insert..." error is the only one I received.Can anyone help me on that issue? Take note that this approach wasused because of customer requirements; the size of the database alsocauses some problem (over 200 tables) and we decided to use the samestructure on both side to minimize the support time.
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May 8, 2008
Hi all,
I'm using SQL Server Express 2005, with mixed authentication mode.
I would like to connect, manipulate data and administrate db's on my server without explicit permissions on those db's.
I've created a new Login with SQL Server authentication and assigned it the public & sysadmin server roles BUT I can't even connect to db's where I don't have an explicit db role (db_owner, ddl_admin...)!
What am I missing?
How can I administrate a db without explicit permissions (db role) on that db?
Thanks,
Assaf
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Sep 15, 2005
for some unknow reasons.. my store proc stop working.. and i got an error.. i have installaed the latest SP4 for SQL server 2000 and still have the problem !any ideas why ?? Message "An explicit value for the identity column in table 'LCMS_Modules' can only be specified when a column list is used and IDENTITY_INSERT is ON."CREATE procedure LCMS_Modules_Add
@PageID int, @ModuleDefID int, @Panename nvarchar(32), @Title nvarchar(128), @Admins nvarchar(256)
as
insert into LCMS_Modulesvalues(@PageID, @ModuleDefID, 99, @Panename, @Title, '0;', @Admins, 0, '', 'Center', '', '', '', 1, 0)GO
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Jul 12, 2006
I have a DTS that pulls a file from a networked drive (generally using the u: designation) for part of its process. Recently, the server has been dropping network drive connections, so sometimes the DTS will fail (I'm not certain why it's dropping the connections, nor do I have the access or control to figure out such.)
I've been told that I should change the DTS package to use an explicit path (i.e., \serverfolder1folder2file.mdb instead of u:folder2file.mdb) to work around this problem. However, Enterprise Manager doesn't seem to like using this for the "File name" attribute in the connection properties. (This is an Access connection, if that matters.)
Is there any way to get the explicit path (probably the wrong terminology here) to work with the connection properties?
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Jan 31, 2006
I'm attempting to use FOR XML EXPLICIT in SQLServer to adhere to the following template:
<group>
<sourceid>
<source></source>
<id></id>
<grouptype>
<scheme></scheme>
<typevalue></typevalue>
</grouptype>
<description>
<short></short>
<long></long>
</descrption>
</group>
Here's my code:
SELECT 1 as Tag,
NULL as Parent,
@p_school_desc as [sourceid!1!source!element],
@p_term_code as [sourceid!1!id!element],
NULL as [grouptype!1!scheme!element],
NULL as [grouptype!1!typevalue!element],
NULL as [description!1!short!element],
NULL as [description!1!long!element]
FROM course_main AS sourceid
where sourceid.course_id = @p_course
UNION
SELECT 1 as Tag,
NULL as Parent,
NULL,
NULL,
@p_destination as [grouptype!2!scheme!element],
'Term' as [grouptype!2!typevalue!element],
NULL,
NULL
FROM course_main AS grouptype
where grouptype.course_id = @p_course
UNION
SELECT 1 as Tag,
NULL as Parent,
NULL,
NULL,
NULL,
NULL,
@p_term_code as [description!2!short!element],
@p_term_description as [description!2!long!element]
FROM course_main AS grouptype
where grouptype.course_id = @p_course
FOR XML EXPLICIT
I'm receiving the foollowing error:
Server: Msg 6812, Level 16, State 1, Line 14
XML tag ID 1 that was originally declared as 'sourceid' is being redeclared as 'grouptype'.
Is there anyway to have two different child notes off of the same parent node?
Thanks in advance!
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Jan 31, 2006
I'm attempting to use FOR XML EXPLICIT in SQLServer to adhere to the following template:
<group>
<sourceid>
<source></source>
<id></id>
<grouptype>
<scheme></scheme>
<typevalue></typevalue>
</grouptype>
<description>
<short></short>
<long></long>
</descrption>
</group>
Here's my code:
SELECT 1 as Tag,
NULL as Parent,
@p_school_descas [sourceid!1!source!element],
@p_term_code as [sourceid!1!id!element],
NULLas [grouptype!1!scheme!element],
NULLas [grouptype!1!typevalue!element],
NULLas [description!1!short!element],
NULLas [description!1!long!element]
FROM course_main AS sourceid
where sourceid.course_id = @p_course
UNION
SELECT 1 as Tag,
NULL as Parent,
NULL,
NULL,
@p_destinationas [grouptype!2!scheme!element],
'Term' as [grouptype!2!typevalue!element],
NULL,
NULL
FROM course_main AS grouptype
where grouptype.course_id = @p_course
UNION
SELECT 1 as Tag,
NULL as Parent,
NULL,
NULL,
NULL,
NULL,
@p_term_codeas [description!2!short!element],
@p_term_descriptionas [description!2!long!element]
FROM course_main AS grouptype
where grouptype.course_id = @p_course
FOR XML EXPLICIT
I'm receiving the foollowing error:Server: Msg 6812, Level 16, State 1, Line 14
XML tag ID 1 that was originally declared as 'sourceid' is being redeclared as 'grouptype'.
Is there anyway to have two different child notes off of the same parent node?
Thanks in advance!
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Apr 16, 2008
Hi,
Is it possible to format any kind of XML file with the FOR XML EXPLICIT mode in SQL Server 2005? I am asking because I am trying to format my file in a way that I could get 2 or 3 elements on my parent or child level and put some attributes (icon path for example) in these 2nd element or 3rd element. I am unable to format it that way. Let me show you the way that I would like to have my XML file formated :
<?xml version="1.0" encoding="UTF-8" ?>
<rows>
<row id="14" sort="parent">
<cell icon="../../images/TreeGrid/folder.gif">Operations</cell>
<row id="14.13" sort=”child”>
<cell icon="../../images/TreeGrid/Red.gif">% SP</cell>
<row id="14.13.1" sort=”sub-child”>
<cell icon="../../images/TreeGrid/Red.gif">% SP Sub</cell>
I want to have all my parent, children, sub-children to have these attribut but I am having difficulty putting one in the “Cell” tags. And I really think that my problem resides in the specifying of my column and their directives but I do not know how to fix it. See my icon path is commented here. I have to put the [row!2!cell!xmltext], but it is not working.
Here is the way that I am building my Select query.
SELECT
1 as tag,
NULL as parent,
NULL AS 'rows!1!', ----Root rows tag
ID_metric as [row!2!id],
Description_english as [row!2!cell!Element],
----Icon as [row!2!cell!xmltext],
Sort as [row!2!sort],
ID_metric as [row!3!id],
Description_english as [row!3!cell!Element],
--Icon as [row!3!cell!xmltext],
sort as [row!3!sort],
ID_metric as [row!4!id],
Description_english as [row!4!cell!Element],
--Icon as [row!4!cell!xmltext],
sort as [row!4!sort],
ID_metric as [row!5!id],
Description_english as [row!5!cell!Element],
--Icon as [row!5!cell!xmltext],
sort as [row!5!sort],
FROM #buildData
WHERE HLevel = 0
UNION ALL
SELECT
2 as tag,
1 as parent,
NULL AS 'rows!1!',
ID_metric as [row!2!id],
Description_english as [row!2!cell!Element],
--Icon as [row!2!cell!xmltext],
sort as [row!2!sort],
ID_metric as [row!3!id],
Description_english as [row!3!cell!Element],
--Icon as [row!3!cell!xmltext],
sort as [row!3!sort],
ID_metric as [row!4!id],
Description_english as [row!4!cell!Element],
--Icon as [row!4!cell!xmltext],
sort as [row!4!sort],
ID_metric as [row!5!id],
Description_english as [row!5!cell!Element],
--Icon as [row!5!cell!xmltext],
sort as [row!5!sort],
FROM #buildData
WHERE HLevel = 1
UNION ALL
SELECT
3 as tag,
2 as parent,
NULL AS 'rows!1!',
ID_metric as [row!2!id],
Description_english as [row!2!cell!Element],
--Icon as [row!2!cell!xmltext],
sort as [row!2!sort],
ID_metric as [row!3!id],
Description_english as [row!3!cell!Element],
--Icon as [row!3!cell!xmltext],
sort as [row!3!sort],
ID_metric as [row!4!id],
Description_english as [row!4!cell!Element],
--Icon as [row!4!cell!xmltext],
sort as [row!4!sort],
ID_metric as [row!5!id],
Description_english as [row!5!cell!Element],
--Icon as [row!5!cell!xmltext],
sort as [row!5!sort],
FROM #buildData
WHERE HLevel = 2
UNION ALL
SELECT
4 as tag,
3 as parent,
NULL AS 'rows!1!',
ID_metric as [row!2!id],
Description_english as [row!2!cell!Element],
--Icon as [row!2!cell!xmltext],
sort as [row!2!sort],
ID_metric as [row!3!id],
Description_english as [row!3!cell!Element],
--Icon as [row!3!cell!xmltext],
sort as [row!3!sort],
ID_metric as [row!4!id],
Description_english as [row!4!cell!Element],
--Icon as [row!4!cell!xmltext],
sort as [row!4!sort],
ID_metric as [row!5!id],
Description_english as [row!5!cell!Element],
--Icon as [row!5!cell!xml],
sort as [row!5!sort],
FROM #buildData
WHERE HLevel = 3
ORDER BY [row!2!sort], [row!3!sort], [row!4!sort], [row!5!sort]
for XML explicit
My actual XML Result is this :
<rows>
<row id="14" sort="parent">
<cell>% SP</cell>
<row id="14.13" sort="child">
<cell>% SP </cell>
<row id="14.13.1" sort="child">
<cell>% SP cild </cell>
Is it possible to customized anything with For XML Explicit?
Anybody that can help my with that or indicate me where I am doing wrong? Thanks a lot.
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Jul 9, 2014
SQL 2012R2 Std. I have a sql statement to retrieve data in XML format. I have to use EXPLICIT because I have to use tag <CDATA>
I would like to store the XML returned into 1 column containing the XML tags.
For example:
#tmpXML
row 1: <DOC><NET_INFO net_ID=34><NOTES><![CDATA[description]]></NOTES></NET_INFO></DOC>
row 2 <DOC><NET_INFO net_ID=35><NOTES><![CDATA[description2]]></NOTES></NET_INFO></DOC>
select *
into #tmpXML
FROM (SELECT 1 AS Tag
[Code] ....
But I keep getting an error message:
The FOR XML clause is invalid in views, inline functions, derived tables, and subqueries when they contain a set operator. To work around, wrap the SELECT containing a set operator using derived table syntax and apply FOR XML on top of it.
I have tried a couple of other ways but continue to get an error message.
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Oct 25, 2006
Hello Everyone,
I am trying to insert a new record into a sql table and I get the following error message:
Msg 544, Level 16, State 1, Line 1
Cannot insert explicit value for identity column in table 'tbl_MLS_ReportCriteria' when IDENTITY_INSERT is set to OFF.
Here is the code:
USE MLS
INSERT INTO dbo.tbl_MLS_ReportCriteria (CriteriaID, Name, DisplayName, DetailedInstructions, TypeID, Source, DefaultValue, ValueField, DescriptionField, IncludeAllOption)
VALUES ('65', 'Summary3', 'Tertiary Summarize By', NULL, '2', 'SelectOptions', 'Company', NULL, NULL, '0')
What do I need to change and or look for?
TIA
Kurt
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Mar 31, 2008
Is there any difference between explicit inner join and implicitinner joinExample of an explicit inner join:SELECT *FROM employeeINNER JOIN departmentON employee.DepartmentID = department.DepartmentIDExample of an implicit inner join:SELECT *FROM employee, departmentWHERE employee.DepartmentID = department.DepartmentID
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Sep 19, 2005
I gave a developer rights to the Public role on a SQL Server 2000 database. The Public role only has explicitly set select rights to the system tables and one user table. There are no other explicit rights set. The developer was able to open a table that had no rights set in enterprise manager and change data. Is this possible?
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May 30, 2008
Hi
What is SQL Server 2005 default behavior with statement like this:
SELECT * FROM dbo.Products
Will it take any shared locks on Products table? Is it different than:
BEGIN TRAN
SELECT * FROM dbo.Products WITH NOLOCK
COMMIT
TIA
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May 6, 2008
Hi,
Is it possible to explicitly insert a value into an identity column??
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Nov 1, 2006
Hi,
I am trying to create a XML out of sql 2005 database using FOR XML. I
need to create XML for tables which may contain data having
non-printable ascii characters (1-32 ascii character). I found FOR XML
AUTO failes to genrate this XML, but i can genrate XML using CDATA
section in FOR XML EXPLICIT. As following querie works fine for me.
SELECT
1 AS tag
NULL AS parent,
template_id AS [Emailqueue!1!user_id],
misc1 AS [Emailqueue!1!!cdata]
FROM Emailqueue WITH (NOLOCK)
WHERE queue_id = -2147483169
FOR XML EXPLICIT
in above query misc1 column may contain some non printable ascii
characters.
But i need to store this XML data in some sql XML variable as i need to
pass it to store procedure which expects an xml input. While doing
following i gets an error saying "illegal xml character"
DECLARE @XMLMessage XML
SET @XMLMessage = (SELECT
1 AS tag
NULL AS parent,
template_id AS [Emailqueue!1!user_id],
misc1 AS [Emailqueue!1!!cdata]
FROM Emailqueue WITH (NOLOCK)
WHERE queue_id = -2147483169
FOR XML EXPLICIT)
I am doing all this exercise for SQL service broker. For which i even
need to process same message using OPENXML on differen database server.
Again which will need well formated XML.
Let me know if something dose'nt make sense
any help is appreciated
Thanks
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Dec 14, 2004
Cannot insert explicit value for identity column in table 'tblUsed' when IDENTITY_INSERT is set to OFF.
:confused:
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Jul 20, 2005
Could some database expert post some information or link about that?thanksJanusz
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Feb 27, 2008
Hi there,
I was wondering if someone could propose a solution for the following scenario:
TimeID column would have values from 1 to 6 and rows will be inserted only for those timeIDs where we have Data value as well. While retrieving data we would like to have all timeID range returned with explicitly specifying NULL for missing Data column. Please see below to better understand the situation.
create table test
(
TimeID INT,
Data INT
)
INSERT INTO test VALUES(1, 100)
INSERT INTO test VALUES(2, 180)
INSERT INTO test VALUES(4, 550)
INSERT INTO test VALUES(6, 120)
select * from test
1 100
2 180
4 550
6 120
Desired resultset
1 100
2 180
3 NULL
4 550
5 NULL
6 120
...
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Mar 19, 2014
I have a table called Appointment, for storing (you guessed it) appointments at a medical practice. If an appointment is cancelled, I want to collect a cancellation reason, so let's say that I create a second table called Cancellation which has a foreign key relating to the Appointment table's primary key, AppointmentID, and another column, Reason. Now, in order to indicate that an appointment was cancelled, I could include a Cancelled column in the Appointment table with a bit datatype, or instead I could infer that an appointment must be cancelled if it has a corresponding record in the Cancellation table.
It may be that it'd be better to store the cancellation reason in the Appointment table - But regardless, let's say I stick with the two-table solution described above, and I subsequently want to write a query to list all appointments which have been cancelled. If I had the Cancelled column in the Appointment table, I could simply query for all records in that table where that column's value was FALSE. If I went the other way and DIDN'T have a Cancelled column, I could instead write a query joining the Appointment and Cancellation tables to return all records in Appointment with a corresponding record in Cancellation.
That latter method, whilst slightly more complicated because it involves joining two tables, seems to me to be the most normalised. Instead of storing the fact that an appointment is cancelled in two different tables, that fact is only stored in the Cancellation table. Would there be a performance hit in using the two-table, 'inferred cancellation' method rather than just having a bit column in the Appointment table? Would that performance hit be enough to persuade you to use a Cancellation column in the Appointment table instead? And what about if I were to apply that method to other things associated with each appointment, e.g. Is it completed? Is it chargeable to the client or an insurance company? Is the client and in-patient or out-patient?
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