Custom protection of rows (problem with updatability of viwes with "WITH VIEW_METADATA" an

My question is connected with tip "Using Views to Control User Access to
Data":
http://www.microsoft.com/sql/techinfo/tips/administration/controlledaccess.asp
I need to update (using Access 2000/2002) table defended in such way,
but it cause some additional problems.
1. I can't update this view when user haven't SELECT permissions
on the base table (user have only permissions to the view, because I try to
defend base table).
As I understand ADO tries directly update base table and fails.
2. When I add "WITH VIEW_METADATA" to enforce ADO to update
view, not base tables I have another problem - I need to add
prymary key columns from "authtable" to make view updateble
for ADO. In such way I also had to add some additional procedures
to dataform in Access to fill this additional columns automatically (for
insert operation).
It helps but it cause additional procedures at client side.
3. The best way to resolve this problem only on server side as I thought
was to create view like this (using "WITH VIEW_METADATA" and "IN" clauses):
CREATE VIEW v_data
WITH VIEW_METADATA
AS
SELECT <column_list>
FROM dbo.mytable AS a
WHERE a.Pkey
IN
(
SELECT b.DataKey
FROM dbo.authtable AS b
WHERE b.userid = suser_sname()
)
But this view is not updatable in Access 2000/2002
because ADO DOES NOT SEE PRIMARY KEY INFORMATION
when there is combination "WITH VIEW_METADATA" and "IN" clauses.
I cann't use this view without "WITH VIEW_METADATA", in this case
view is "updatable" for ADO, but updates fails as described in p.1.
I send this bug year ago to MS when was mdac 2.7.
Now we have MDAC 2.8, SQL SP 3, Yukon Beta - ADO has the same problem with
updates
when there is combination "WITH VIEW_METADATA" and "IN" clauses
I think, it helps to make simple customised rowbased security system not
only for SELECT
but also for INSERT, UPDATE and DELETE in combination "SQL Server - MS
Access" or other ADO based clients.Hello Max:
You wrote on Wed, 28 Apr 2004 19:37:02 +0300:
ii> 1. I can't update this view when user haven't SELECT permissions
ii> on the base table (user have only permissions to the view, because I
ii> try to defend base table).
ii> As I understand ADO tries directly update base table and fails.
In Access 2002, open the view in design mode, open properties, select
"Update using view rules".
ÿê òàì Ëüâiâ? ÿ òàì â÷èâñÿ.
Vadim
---
Vadim Rapp Consulting
SQL, Access, VB Solutions
847-685-9073
www.vadimrapp.com|||"Vadim Rapp" <vrapp@.nospam.polyscience.com> ñîîáùèë/ñîîáùèëà â íîâîñòÿõ
ñëåäóþùåå: news:e1IXvQULEHA.2456@.TK2MSFTNGP12.phx.gbl...
> Hello Max:
> You wrote on Wed, 28 Apr 2004 19:37:02 +0300:
> ii> 1. I can't update this view when user haven't SELECT permissions
> ii> on the base table (user have only permissions to the view, because I
> ii> try to defend base table).
> ii> As I understand ADO tries directly update base table and fails.
> In Access 2002, open the view in design mode, open properties, select
> "Update using view rules".
> ÿê òàì Ëüâiâ? ÿ òàì â÷èâñÿ.
> Vadim
> ---
> Vadim Rapp Consulting
> SQL, Access, VB Solutions
> 847-685-9073
> www.vadimrapp.com
>
Hello Vadim,
Thanks for reply,
Chekbox "Update using view rules" exactly adds "WITH VIEW_METADATA" clause
to view definition and this situation adds aditional problems as described
in p.2. But when I want add more sophisticated rules for user selection
permissions and make it updatable in Access I get very processor time
cosuming solutions. Execution plans for view scheme discribed in p.3 for my
tasks and needed rules some times more than 10 time quick than the same that
Access (ADO) understands as updatable - this the main problem...
And root of problem is ADO uncorrect understanding of combination of clauses
"WITH VIEW_METADATA" and "IN" (also "EXISTS").
Ó Ëüâîâ³ êëàñíî, ïðàâäà ùå òðîõè çèìíî áóâàº, ³ ÷àñ â³ä ÷àñó äîùèòü. Â
íåä³ëþ 2 òðàâíÿ áóäåìî ñâÿòêóâàòè äåíü ì³ñòà.
MAX|||Hello Max:
You wrote in conference microsoft.public.sqlserver.server on Thu, 29 Apr
2004 14:05:18 +0300:
II> And root of problem is ADO uncorrect understanding of combination of
II> clauses "WITH VIEW_METADATA" and "IN" (also "EXISTS").
It looks like it's not ADO but Access. I see that Access indeed does not
allow to add records to such a view; however, I successfully executed the
following pure ado code in VB:
rs.CursorLocation = adUseClient
rs.Open "view1", conn, adOpenKeyset, adLockBatchOptimistic
rs.AddNew
rs!c1 = "a"
rs!c2 = "b"
rs!id = 14
rs.UpdateBatch
rs.Close
where view1 was
ALTER VIEW dbo.View1
WITH VIEW_METADATA
AS
SELECT dbo.t1.c1, dbo.t1.c2, dbo.t1.id, dbo.t1.auth
FROM dbo.t1 INNER JOIN
dbo.authtable ON dbo.t1.auth >= dbo.authtable.minvalue
WHERE (dbo.authtable.userid = USER_NAME())
Note that I did not include in the view anything from authtable.
Another interesting possibility is described in BOL in "Create View"
article, which says: "INSTEAD OF triggers can be created on a view in order
to make a view updatable".
As a side note: you might receive more advise if you asked the question in
more relevant newsgroups. This one is mainly read by server administrators;
you might try .access.adp.sqlserver and .data.ado (though, as I said, it
looks like ADO is innocent here).
Êðiì òîãî, êîëè òè ïèøåø â àíãëiéñüêó ãðóïïó, òî ïèøè ñâîº iì'ÿ
ïî-àíãë³éñüêè.
regards,
Vadim
---
Vadim Rapp Consulting
SQL, Access, VB Solutions
847-685-9073
www.vadimrapp.com