Creating an Audit trail on a table using a trigger

Hi,
This is kind of following on from my last couple of posts regarding Identity
columns and so on.
Basically, I want to ensure that for a particular table, every row has a
numeric reference. This reference must be unique and gapless. Ideally it
should order in the sequence of the records being inserted however this
isn't an absolute requirement.
From my (limited) understanding of SQLS, I think I can achieve this with a
FOR INSERT Trigger - in that the trigger is fired every time a row is
inserted and the trigger is the same transaction as the initial insert hence
I avoid any concurrency issues.
However I'm not completely sure how to achieve this. I think that my trigger
should be along the lines of this...
CREATE TRIGGER AssignAuditReference ON tblBooking
FOR INSERT
AS
DECLARE @.Ref int
--Get the highest reference and add one.
SELECT @.Ref = isnull(max(job_id),0)+1 from tblBooking
--Update the inserted row to have a booking_referecen of the new reference
obtained above.
Update tblBooking
SET Booking_Reference = @.ref
WHERE Booking_ID = INSERTED.Booking_ID
However I'm getting problems with the INSERTED table not being recognised.
I understood that the INSERTED table contained the row that the insert that
started the trigger inserted.
Two questions:
1. Where am I going wrong with my trigger. Have I misunderstood some key
point of using triggers.
2. Is this the right approach to achieve what I am after? Are there any
better approaches...Hi Chris,
You have to mention the Inserted Table in your Update Query
Update tblBooking
SET tblBooking.Booking_Reference = @.Ref
FROM tblBooking
INNER JOIN INSERTED
ON (tblBooking.Booking_ID= INSERTED.Booking_ID)
Because of the lack between getting the @.Ref-Value and writing it in the
table i would prefer an inline Query and Update
Update tblBooking
SET tblBooking.Booking_Reference = NewJobIdTable.NewJobId
FROM tblBooking,
(
Select ISNULL(MAX(job_id),0)+1 AS NewJobId from tblBooking
) NewJobIdTable
INNER JOIN INSERTED
ON (tblBooking.Booking_ID= INSERTED.Booking_ID)
HTH, Jens Smeyer.
http://www.sqlserver2005.de
--
"Chris Strug" <hotmail@.solace1884.com> schrieb im Newsbeitrag
news:eBcd9GOQFHA.1392@.TK2MSFTNGP10.phx.gbl...
> Hi,
> This is kind of following on from my last couple of posts regarding
> Identity
> columns and so on.
> Basically, I want to ensure that for a particular table, every row has a
> numeric reference. This reference must be unique and gapless. Ideally it
> should order in the sequence of the records being inserted however this
> isn't an absolute requirement.
> From my (limited) understanding of SQLS, I think I can achieve this with a
> FOR INSERT Trigger - in that the trigger is fired every time a row is
> inserted and the trigger is the same transaction as the initial insert
> hence
> I avoid any concurrency issues.
> However I'm not completely sure how to achieve this. I think that my
> trigger
> should be along the lines of this...
> CREATE TRIGGER AssignAuditReference ON tblBooking
> FOR INSERT
> AS
> DECLARE @.Ref int
> --Get the highest reference and add one.
> SELECT @.Ref = isnull(max(job_id),0)+1 from tblBooking
> --Update the inserted row to have a booking_referecen of the new
> reference
> obtained above.
> Update tblBooking
> SET Booking_Reference = @.ref
> WHERE Booking_ID = INSERTED.Booking_ID
> However I'm getting problems with the INSERTED table not being recognised.
> I understood that the INSERTED table contained the row that the insert
> that
> started the trigger inserted.
> Two questions:
> 1. Where am I going wrong with my trigger. Have I misunderstood some key
> point of using triggers.
> 2. Is this the right approach to achieve what I am after? Are there any
> better approaches...
>|||Syntactically, your UPDATE statement is missing the FROM clasue:
UPDATE tblBooking
SET Booking_Reference = @.ref
FROM tblBooking , INSERTED
WHERE Booking_ID = INSERTED.Booking_ID
1) This will FAIL if more than one row is inserted - not a good idea
for maintaining an audit trail. 2) I don't see what advantage this has
over the more concise and reliable solution(s) already discussed in
your earlier threads. For example:
INSERT INTO tblBooking (booking_reference, x, y, z, ...)
SELECT COALESCE(MAX(booking_reference),0)+1, 'foo', 'bar', 1234, ...
FROM tblBooking
IMO an incrementing counter is a poor way to maintain an audit trail
anyway. Why not just store the CURRENT_TIMESTAMP on each row and then
preserve the history of changes to rows? This is easy to do in triggers
or in your data access code and doesn't suffer the inevitable and
serious blocking problems that your approach implies.
David Portas
SQL Server MVP
--|||"David Portas" <REMOVE_BEFORE_REPLYING_dportas@.acm.org> wrote in message
news:1113478283.991829.222620@.g14g2000cwa.googlegroups.com...
> Syntactically, your UPDATE statement is missing the FROM clasue:
> UPDATE tblBooking
> SET Booking_Reference = @.ref
> FROM tblBooking , INSERTED
> WHERE Booking_ID = INSERTED.Booking_ID
> 1) This will FAIL if more than one row is inserted - not a good idea
> for maintaining an audit trail. 2) I don't see what advantage this has
> over the more concise and reliable solution(s) already discussed in
> your earlier threads. For example:
> INSERT INTO tblBooking (booking_reference, x, y, z, ...)
> SELECT COALESCE(MAX(booking_reference),0)+1, 'foo', 'bar', 1234, ...
> FROM tblBooking
> IMO an incrementing counter is a poor way to maintain an audit trail
> anyway. Why not just store the CURRENT_TIMESTAMP on each row and then
> preserve the history of changes to rows? This is easy to do in triggers
> or in your data access code and doesn't suffer the inevitable and
> serious blocking problems that your approach implies.
> --
> David Portas
> SQL Server MVP
> --
>
First of all thanks to both David and Jens for their replies.
Apologies for repeating myself, I just want to make sure that I understand
what I'm doing rather than repeating it parrot fashion into my database.
Regarding the trigger, I was under the impression that the trigger would
occur for every new row, I gather that it in fact applies to every INSERT.
Ahh... That makes things clearer.
Regards the actual implementation (TIMESTAMP vs. numeric reference),
unfortunately this is out of my hands. I've been informed that this a is a
non negotiatable requirement. What can you do?
if I may ask one more question, assuming that I did attempt to implement my
apprioach using triggers, could you expand on the blocking problems that you
would expect me to face?
Anyway, thank you once again for taking the time to help me, I do appreciate
it.
Regards
Chris.

Creating a trigger for the row being updated

Hello group,
I have a question regarding an update trigger.
For example, I have the following fields in a table..
ItemCode
ShortDescription
Quantity
UpdatedDate
UpdatedBy
I want to create a trigger that updates the "UpdatedDate" and
"UpdatedBy" fields when either the "ShortDescription" or "Quantity"
fields get updated.
I have figured out how to use the "bitwise" operators so as to target
only columns 2 and 3 for chages, however, telling the trigger to only
update the records which has been changed is proving to be a
challenge.
Thanks in advance
Leenux_tux
Try:
update m
set
UpdatedDate = getdate ()
, UpdatedBy = CURRENT_USER
from
MyTable m
join
inserted i on i.ItemCode = m.ItemCode
join
deleted d on d.ItemCode = i.ItemCode
where
i.ShortDescription <> d.ShortDescription
or i.Quantity <> d.Quantity
Tom
Thomas A. Moreau, BSc, PhD, MCSE, MCDBA, MCITP, MCTS
SQL Server MVP
Toronto, ON Canada
https://mvp.support.microsoft.com/profile/Tom.Moreau
"leenux_tux" <nigel.henderson@.connecta.ltd.uk> wrote in message
news:1181137271.655691.191540@.m36g2000hse.googlegr oups.com...
Hello group,
I have a question regarding an update trigger.
For example, I have the following fields in a table..
ItemCode
ShortDescription
Quantity
UpdatedDate
UpdatedBy
I want to create a trigger that updates the "UpdatedDate" and
"UpdatedBy" fields when either the "ShortDescription" or "Quantity"
fields get updated.
I have figured out how to use the "bitwise" operators so as to target
only columns 2 and 3 for chages, however, telling the trigger to only
update the records which has been changed is proving to be a
challenge.
Thanks in advance
Leenux_tux
|||leenux_tux,
Assuming that ItemCode is an unchanging primary key:
UPDATE M
SET UpdatedDate = GETDATE(), UpdatedBy = SUSER_SNAME()
FROM MyTable M
JOIN inserted i
ON M.ItemCode = i.ItemCode
The inserted table contains inserted or updated rows and the deleted table
contains deleted rows. Experience says that this trigger may actually take
more time to run for a single row than the original update ran.
If you are updating the row through a stored procedure (recommended) or
through other controllable code, considering directly supplying the data and
name in the initial update rather than having the trigger do clean up.
RLF
"leenux_tux" <nigel.henderson@.connecta.ltd.uk> wrote in message
news:1181137271.655691.191540@.m36g2000hse.googlegr oups.com...
> Hello group,
> I have a question regarding an update trigger.
> For example, I have the following fields in a table..
> ItemCode
> ShortDescription
> Quantity
> UpdatedDate
> UpdatedBy
> I want to create a trigger that updates the "UpdatedDate" and
> "UpdatedBy" fields when either the "ShortDescription" or "Quantity"
> fields get updated.
> I have figured out how to use the "bitwise" operators so as to target
> only columns 2 and 3 for chages, however, telling the trigger to only
> update the records which has been changed is proving to be a
> challenge.
> Thanks in advance
> Leenux_tux
>
|||The problem with this code is that is does not exactly meet the spec:
'I want to create a trigger that updates the "UpdatedDate" and "UpdatedBy"
fields when either the "ShortDescription" or "Quantity" fields get updated.'
IOW, if both of these columns are set to their original values, the you are
updating the UpdatedDate and UpdatedBy columns, which you don't want to do.
You need to join also on the deleted virtual table and compare the values in
inserted vs. deleted.
Tom
Thomas A. Moreau, BSc, PhD, MCSE, MCDBA, MCITP, MCTS
SQL Server MVP
Toronto, ON Canada
https://mvp.support.microsoft.com/profile/Tom.Moreau
"Russell Fields" <russellfields@.nomail.com> wrote in message
news:uO23zPEqHHA.3948@.TK2MSFTNGP05.phx.gbl...
leenux_tux,
Assuming that ItemCode is an unchanging primary key:
UPDATE M
SET UpdatedDate = GETDATE(), UpdatedBy = SUSER_SNAME()
FROM MyTable M
JOIN inserted i
ON M.ItemCode = i.ItemCode
The inserted table contains inserted or updated rows and the deleted table
contains deleted rows. Experience says that this trigger may actually take
more time to run for a single row than the original update ran.
If you are updating the row through a stored procedure (recommended) or
through other controllable code, considering directly supplying the data and
name in the initial update rather than having the trigger do clean up.
RLF
"leenux_tux" <nigel.henderson@.connecta.ltd.uk> wrote in message
news:1181137271.655691.191540@.m36g2000hse.googlegr oups.com...
> Hello group,
> I have a question regarding an update trigger.
> For example, I have the following fields in a table..
> ItemCode
> ShortDescription
> Quantity
> UpdatedDate
> UpdatedBy
> I want to create a trigger that updates the "UpdatedDate" and
> "UpdatedBy" fields when either the "ShortDescription" or "Quantity"
> fields get updated.
> I have figured out how to use the "bitwise" operators so as to target
> only columns 2 and 3 for chages, however, telling the trigger to only
> update the records which has been changed is proving to be a
> challenge.
> Thanks in advance
> Leenux_tux
>
|||Tom,
You are correct. My mistake.
Of course, if Item_Code is NOT an unchanging primary key, then things still
get interesting.
RLF
"Tom Moreau" <tom@.dont.spam.me.cips.ca> wrote in message
news:%23qS6J8HqHHA.1216@.TK2MSFTNGP03.phx.gbl...
> The problem with this code is that is does not exactly meet the spec:
> 'I want to create a trigger that updates the "UpdatedDate" and "UpdatedBy"
> fields when either the "ShortDescription" or "Quantity" fields get
> updated.'
> IOW, if both of these columns are set to their original values, the you
> are
> updating the UpdatedDate and UpdatedBy columns, which you don't want to
> do.
> You need to join also on the deleted virtual table and compare the values
> in
> inserted vs. deleted.
> --
> Tom
> ----
> Thomas A. Moreau, BSc, PhD, MCSE, MCDBA, MCITP, MCTS
> SQL Server MVP
> Toronto, ON Canada
> https://mvp.support.microsoft.com/profile/Tom.Moreau
>
> "Russell Fields" <russellfields@.nomail.com> wrote in message
> news:uO23zPEqHHA.3948@.TK2MSFTNGP05.phx.gbl...
> leenux_tux,
> Assuming that ItemCode is an unchanging primary key:
> UPDATE M
> SET UpdatedDate = GETDATE(), UpdatedBy = SUSER_SNAME()
> FROM MyTable M
> JOIN inserted i
> ON M.ItemCode = i.ItemCode
> The inserted table contains inserted or updated rows and the deleted table
> contains deleted rows. Experience says that this trigger may actually
> take
> more time to run for a single row than the original update ran.
> If you are updating the row through a stored procedure (recommended) or
> through other controllable code, considering directly supplying the data
> and
> name in the initial update rather than having the trigger do clean up.
> RLF
> "leenux_tux" <nigel.henderson@.connecta.ltd.uk> wrote in message
> news:1181137271.655691.191540@.m36g2000hse.googlegr oups.com...
>
|||That emphasizes the fact that a PK should never change. There are
exceptions, though.
Tom
Thomas A. Moreau, BSc, PhD, MCSE, MCDBA, MCITP, MCTS
SQL Server MVP
Toronto, ON Canada
https://mvp.support.microsoft.com/profile/Tom.Moreau
"Russell Fields" <russellfields@.nomail.com> wrote in message
news:uh5I%23VIqHHA.3892@.TK2MSFTNGP05.phx.gbl...
Tom,
You are correct. My mistake.
Of course, if Item_Code is NOT an unchanging primary key, then things still
get interesting.
RLF
"Tom Moreau" <tom@.dont.spam.me.cips.ca> wrote in message
news:%23qS6J8HqHHA.1216@.TK2MSFTNGP03.phx.gbl...
> The problem with this code is that is does not exactly meet the spec:
> 'I want to create a trigger that updates the "UpdatedDate" and "UpdatedBy"
> fields when either the "ShortDescription" or "Quantity" fields get
> updated.'
> IOW, if both of these columns are set to their original values, the you
> are
> updating the UpdatedDate and UpdatedBy columns, which you don't want to
> do.
> You need to join also on the deleted virtual table and compare the values
> in
> inserted vs. deleted.
> --
> Tom
> ----
> Thomas A. Moreau, BSc, PhD, MCSE, MCDBA, MCITP, MCTS
> SQL Server MVP
> Toronto, ON Canada
> https://mvp.support.microsoft.com/profile/Tom.Moreau
>
> "Russell Fields" <russellfields@.nomail.com> wrote in message
> news:uO23zPEqHHA.3948@.TK2MSFTNGP05.phx.gbl...
> leenux_tux,
> Assuming that ItemCode is an unchanging primary key:
> UPDATE M
> SET UpdatedDate = GETDATE(), UpdatedBy = SUSER_SNAME()
> FROM MyTable M
> JOIN inserted i
> ON M.ItemCode = i.ItemCode
> The inserted table contains inserted or updated rows and the deleted table
> contains deleted rows. Experience says that this trigger may actually
> take
> more time to run for a single row than the original update ran.
> If you are updating the row through a stored procedure (recommended) or
> through other controllable code, considering directly supplying the data
> and
> name in the initial update rather than having the trigger do clean up.
> RLF
> "leenux_tux" <nigel.henderson@.connecta.ltd.uk> wrote in message
> news:1181137271.655691.191540@.m36g2000hse.googlegr oups.com...
>

Creating a trigger for the row being updated

Hello group,
I have a question regarding an update trigger.
For example, I have the following fields in a table..
ItemCode
ShortDescription
Quantity
UpdatedDate
UpdatedBy
I want to create a trigger that updates the "UpdatedDate" and
"UpdatedBy" fields when either the "ShortDescription" or "Quantity"
fields get updated.
I have figured out how to use the "bitwise" operators so as to target
only columns 2 and 3 for chages, however, telling the trigger to only
update the records which has been changed is proving to be a
challenge.
Thanks in advance
Leenux_tuxTry:
update m
set
UpdatedDate = getdate ()
, UpdatedBy = CURRENT_USER
from
MyTable m
join
inserted i on i.ItemCode = m.ItemCode
join
deleted d on d.ItemCode = i.ItemCode
where
i.ShortDescription <> d.ShortDescription
or i.Quantity <> d.Quantity
--
Tom
----
Thomas A. Moreau, BSc, PhD, MCSE, MCDBA, MCITP, MCTS
SQL Server MVP
Toronto, ON Canada
https://mvp.support.microsoft.com/profile/Tom.Moreau
"leenux_tux" <nigel.henderson@.connecta.ltd.uk> wrote in message
news:1181137271.655691.191540@.m36g2000hse.googlegroups.com...
Hello group,
I have a question regarding an update trigger.
For example, I have the following fields in a table..
ItemCode
ShortDescription
Quantity
UpdatedDate
UpdatedBy
I want to create a trigger that updates the "UpdatedDate" and
"UpdatedBy" fields when either the "ShortDescription" or "Quantity"
fields get updated.
I have figured out how to use the "bitwise" operators so as to target
only columns 2 and 3 for chages, however, telling the trigger to only
update the records which has been changed is proving to be a
challenge.
Thanks in advance
Leenux_tux|||leenux_tux,
Assuming that ItemCode is an unchanging primary key:
UPDATE M
SET UpdatedDate = GETDATE(), UpdatedBy = SUSER_SNAME()
FROM MyTable M
JOIN inserted i
ON M.ItemCode = i.ItemCode
The inserted table contains inserted or updated rows and the deleted table
contains deleted rows. Experience says that this trigger may actually take
more time to run for a single row than the original update ran.
If you are updating the row through a stored procedure (recommended) or
through other controllable code, considering directly supplying the data and
name in the initial update rather than having the trigger do clean up.
RLF
"leenux_tux" <nigel.henderson@.connecta.ltd.uk> wrote in message
news:1181137271.655691.191540@.m36g2000hse.googlegroups.com...
> Hello group,
> I have a question regarding an update trigger.
> For example, I have the following fields in a table..
> ItemCode
> ShortDescription
> Quantity
> UpdatedDate
> UpdatedBy
> I want to create a trigger that updates the "UpdatedDate" and
> "UpdatedBy" fields when either the "ShortDescription" or "Quantity"
> fields get updated.
> I have figured out how to use the "bitwise" operators so as to target
> only columns 2 and 3 for chages, however, telling the trigger to only
> update the records which has been changed is proving to be a
> challenge.
> Thanks in advance
> Leenux_tux
>|||The problem with this code is that is does not exactly meet the spec:
'I want to create a trigger that updates the "UpdatedDate" and "UpdatedBy"
fields when either the "ShortDescription" or "Quantity" fields get updated.'
IOW, if both of these columns are set to their original values, the you are
updating the UpdatedDate and UpdatedBy columns, which you don't want to do.
You need to join also on the deleted virtual table and compare the values in
inserted vs. deleted.
--
Tom
----
Thomas A. Moreau, BSc, PhD, MCSE, MCDBA, MCITP, MCTS
SQL Server MVP
Toronto, ON Canada
https://mvp.support.microsoft.com/profile/Tom.Moreau
"Russell Fields" <russellfields@.nomail.com> wrote in message
news:uO23zPEqHHA.3948@.TK2MSFTNGP05.phx.gbl...
leenux_tux,
Assuming that ItemCode is an unchanging primary key:
UPDATE M
SET UpdatedDate = GETDATE(), UpdatedBy = SUSER_SNAME()
FROM MyTable M
JOIN inserted i
ON M.ItemCode = i.ItemCode
The inserted table contains inserted or updated rows and the deleted table
contains deleted rows. Experience says that this trigger may actually take
more time to run for a single row than the original update ran.
If you are updating the row through a stored procedure (recommended) or
through other controllable code, considering directly supplying the data and
name in the initial update rather than having the trigger do clean up.
RLF
"leenux_tux" <nigel.henderson@.connecta.ltd.uk> wrote in message
news:1181137271.655691.191540@.m36g2000hse.googlegroups.com...
> Hello group,
> I have a question regarding an update trigger.
> For example, I have the following fields in a table..
> ItemCode
> ShortDescription
> Quantity
> UpdatedDate
> UpdatedBy
> I want to create a trigger that updates the "UpdatedDate" and
> "UpdatedBy" fields when either the "ShortDescription" or "Quantity"
> fields get updated.
> I have figured out how to use the "bitwise" operators so as to target
> only columns 2 and 3 for chages, however, telling the trigger to only
> update the records which has been changed is proving to be a
> challenge.
> Thanks in advance
> Leenux_tux
>|||Tom,
You are correct. My mistake.
Of course, if Item_Code is NOT an unchanging primary key, then things still
get interesting.
RLF
"Tom Moreau" <tom@.dont.spam.me.cips.ca> wrote in message
news:%23qS6J8HqHHA.1216@.TK2MSFTNGP03.phx.gbl...
> The problem with this code is that is does not exactly meet the spec:
> 'I want to create a trigger that updates the "UpdatedDate" and "UpdatedBy"
> fields when either the "ShortDescription" or "Quantity" fields get
> updated.'
> IOW, if both of these columns are set to their original values, the you
> are
> updating the UpdatedDate and UpdatedBy columns, which you don't want to
> do.
> You need to join also on the deleted virtual table and compare the values
> in
> inserted vs. deleted.
> --
> Tom
> ----
> Thomas A. Moreau, BSc, PhD, MCSE, MCDBA, MCITP, MCTS
> SQL Server MVP
> Toronto, ON Canada
> https://mvp.support.microsoft.com/profile/Tom.Moreau
>
> "Russell Fields" <russellfields@.nomail.com> wrote in message
> news:uO23zPEqHHA.3948@.TK2MSFTNGP05.phx.gbl...
> leenux_tux,
> Assuming that ItemCode is an unchanging primary key:
> UPDATE M
> SET UpdatedDate = GETDATE(), UpdatedBy = SUSER_SNAME()
> FROM MyTable M
> JOIN inserted i
> ON M.ItemCode = i.ItemCode
> The inserted table contains inserted or updated rows and the deleted table
> contains deleted rows. Experience says that this trigger may actually
> take
> more time to run for a single row than the original update ran.
> If you are updating the row through a stored procedure (recommended) or
> through other controllable code, considering directly supplying the data
> and
> name in the initial update rather than having the trigger do clean up.
> RLF
> "leenux_tux" <nigel.henderson@.connecta.ltd.uk> wrote in message
> news:1181137271.655691.191540@.m36g2000hse.googlegroups.com...
>> Hello group,
>> I have a question regarding an update trigger.
>> For example, I have the following fields in a table..
>> ItemCode
>> ShortDescription
>> Quantity
>> UpdatedDate
>> UpdatedBy
>> I want to create a trigger that updates the "UpdatedDate" and
>> "UpdatedBy" fields when either the "ShortDescription" or "Quantity"
>> fields get updated.
>> I have figured out how to use the "bitwise" operators so as to target
>> only columns 2 and 3 for chages, however, telling the trigger to only
>> update the records which has been changed is proving to be a
>> challenge.
>> Thanks in advance
>> Leenux_tux
>|||That emphasizes the fact that a PK should never change. There are
exceptions, though.
--
Tom
----
Thomas A. Moreau, BSc, PhD, MCSE, MCDBA, MCITP, MCTS
SQL Server MVP
Toronto, ON Canada
https://mvp.support.microsoft.com/profile/Tom.Moreau
"Russell Fields" <russellfields@.nomail.com> wrote in message
news:uh5I%23VIqHHA.3892@.TK2MSFTNGP05.phx.gbl...
Tom,
You are correct. My mistake.
Of course, if Item_Code is NOT an unchanging primary key, then things still
get interesting.
RLF
"Tom Moreau" <tom@.dont.spam.me.cips.ca> wrote in message
news:%23qS6J8HqHHA.1216@.TK2MSFTNGP03.phx.gbl...
> The problem with this code is that is does not exactly meet the spec:
> 'I want to create a trigger that updates the "UpdatedDate" and "UpdatedBy"
> fields when either the "ShortDescription" or "Quantity" fields get
> updated.'
> IOW, if both of these columns are set to their original values, the you
> are
> updating the UpdatedDate and UpdatedBy columns, which you don't want to
> do.
> You need to join also on the deleted virtual table and compare the values
> in
> inserted vs. deleted.
> --
> Tom
> ----
> Thomas A. Moreau, BSc, PhD, MCSE, MCDBA, MCITP, MCTS
> SQL Server MVP
> Toronto, ON Canada
> https://mvp.support.microsoft.com/profile/Tom.Moreau
>
> "Russell Fields" <russellfields@.nomail.com> wrote in message
> news:uO23zPEqHHA.3948@.TK2MSFTNGP05.phx.gbl...
> leenux_tux,
> Assuming that ItemCode is an unchanging primary key:
> UPDATE M
> SET UpdatedDate = GETDATE(), UpdatedBy = SUSER_SNAME()
> FROM MyTable M
> JOIN inserted i
> ON M.ItemCode = i.ItemCode
> The inserted table contains inserted or updated rows and the deleted table
> contains deleted rows. Experience says that this trigger may actually
> take
> more time to run for a single row than the original update ran.
> If you are updating the row through a stored procedure (recommended) or
> through other controllable code, considering directly supplying the data
> and
> name in the initial update rather than having the trigger do clean up.
> RLF
> "leenux_tux" <nigel.henderson@.connecta.ltd.uk> wrote in message
> news:1181137271.655691.191540@.m36g2000hse.googlegroups.com...
>> Hello group,
>> I have a question regarding an update trigger.
>> For example, I have the following fields in a table..
>> ItemCode
>> ShortDescription
>> Quantity
>> UpdatedDate
>> UpdatedBy
>> I want to create a trigger that updates the "UpdatedDate" and
>> "UpdatedBy" fields when either the "ShortDescription" or "Quantity"
>> fields get updated.
>> I have figured out how to use the "bitwise" operators so as to target
>> only columns 2 and 3 for chages, however, telling the trigger to only
>> update the records which has been changed is proving to be a
>> challenge.
>> Thanks in advance
>> Leenux_tux
>

CreateReports and Delphi 7

Hello,
I have question regarding the method CreateReports. I develope in Delphi 7
and did the following to call the method (other methods before, like
CreateDatasource work successfully):
procedure TRepServWrapper.PublishRDLFile (const rdlname, rdlfile, parentPath
: String);
var
fs : TFileStream;
byteArray : TByteDynArray;
warnings : ArrayOfWarning;
i : Integer;
begin
fs := TFileStream.Create(rdlfile,fmOpenRead);
SetLength(byteArray,fs.Size + 1);
Try
fs.ReadBuffer(byteArray,fs.Size);
except on e:Exception do
raise ECouldNotOpenRDLFile.Create('TRepServWrapper.PublishRDLFile: ' +
errCouldNotOpenRDLFile + ': '+e.Message);
end;
fs.Free;
Try
warnings := FRSInt.CreateReport(rdlname,parentPath,True,byteArray,nil);
If Not (warnings = nil) Then
begin
for i := 0 to High(warnings)-1 do
SendDebug('Warnung beim Upload der RDL: '+ warnings[i].Message);
end
else
SendDebug('RDL erfolgreich geuploadet!');
except on e : Exception do
raise ECouldNotUploadRDL.Create('TRepServWrapper.PublishRDLFile: ' +
errCouldNotUploadRDL + ': ' + e.Message);
end;
end;
When I compile and run the application nothing happens after the line
warnings := FRSInt.CreateReport(...)..no error message, just nothing!
What could be the reason? Do I have to format the byte array in a different
way? I have seen that it has to be Base64 encoded...is this done
automatically? I took an Visual Basic example and adapted it to Delphi.Me again,
I have solved it: I created the byte array in a wrong way. It would be
correct in the following way:
fs := TFileStream.Create(rdlfile,fmOpenRead);
Try
Try
if fs.Size > 0 Then
begin
SetLength(byteArray, fs.Size);
fs.ReadBuffer(byteArray[0],fs.Size);
end;
except on e:Exception do
raise ECouldNotOpenRDLFile.Create('TRepServWrapper.PublishRDLFile: '
+ errCouldNotOpenRDLFile + ': '+e.Message);
end;
finally
fs.Free;
end;