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You would have to maintain your own metadata. You could, for ease, link it to the existing metadata.
You could create your own metadata table with this schema:
CREATE TABLE MyMetaData
(id int,
colid smallint,
is_bold bit....) -- Add your own metadata as needed
The primary key is on id & colid
id is the iditifier from the sysobjects table (which contains a list of the tables umong other things)
Does this help?
"If a man empties his purse into his head, no man can take it away from him, for an investment in knowledge pays the best interest." -- Joseph E. O'Donnell
Can't manage to P/Invoke that Win32 API in .NET? Why not do interop the wiki way!
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Yes, I think this would work. Thanks a lot, man.
This is a better solution than my original idea, as it is extensible. The only minor problem it would have - if users delete columns from their tables, the corresponding entries will unnecessarily remain in MyMetaData table. But this is a negligible problem.
Anybody else has any better/easier solution?
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I have 2 select statements and both of them return a number, i need to add the result of both of them
Does any one know HOW-TO do this...
Glenn Guzman
San Jose, Costa Rica
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SELECT A.A+B.B
FROM (SELECT 1 as A) AS A
INNER JOIN (SELECT 2 as B) AS B ON 1=1
For this to work each subquery (the selects inside the brackets) must return exactly one row only.
"If a man empties his purse into his head, no man can take it away from him, for an investment in knowledge pays the best interest." -- Joseph E. O'Donnell
Can't manage to P/Invoke that Win32 API in .NET? Why not do interop the wiki way!
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U can try something like
create view vwtest as
select A.X S from Table A where <condition>
union
select B.X S from Table B where <condition>
select sum(S) from vwtest
cool man
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Hi all,
anyone know if there is a way to convert an SQL Server script (i think it's TSQL?) to an Oracle script (i think its PL/SQL)?
Converting it by hand is giving me a royal headache.
Thanx in advance.
Jubjub
If there's one thing I've learned, it's that life is one crushing defeat after another until you just wish Flanders was dead. - Homer Simpson
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I am working on ADO databound dialog where i am calling a database which has 2 tables , in which table 1 is called as ADO and i like to call a frist field of table 2 into the same ADO dailog as a dropdown (Combobox control)which i have already called for frist table.
Please Help in this 
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Problem:
Password text is shown in ConnectionString property of ADODB.Connection when using an OLEDB provider and specifying Persist Security Info=false.
Applies to:
ADO, OLE DB Provider
Description:
According to MSDN documentation: http://msdn.microsoft.com/library/default.asp?url=/library/en-us/adosql/adoprg04_97g9.asp
If Persist Security Info is set to False at the time the data source is initialized, the data source cannot persist sensitive authentication information. Furthermore, a call to a property that contains sensitive authentication information, such as a password, returns a default value instead of the actual password.
After the data source has been uninitialized, sensitive information that was set when the data source was initialized with the Persist Security Info property set to False still cannot be obtained from the Properties collection or by persisting the uninitialized data source object. However, new properties set after the data source object has been uninitialized can be persisted or obtained if Persist Security Info is set to True.
Before the data source is initialized for the first time, sensitive information can be obtained from the Properties collection, and can be persisted, regardless of the setting of the Persist Security Info property. Therefore, sensitive applications should avoid passing uninitialized data source objects.
However, password text is shown in the ConnectionString property after an error occurs or when asking for ConnectionString after the ADO Connection has been closed.
The following code shows how to reproduce the problem:
private sub tryConnection()
Dim adoConn As ADODB.Connection
Dim sSql As String
Dim sConnectionString as String
Dim rstConsulta As ADODB.Recordset
Dim pwd As String
On Error GoTo ErrorHandler
Set adoConn = New ADODB.Connection
Set rstConsulta = New ADODB.Recordset
‘//Any SQL statement
sSql = "select Count(*) from K_User " '//Change this for a valid statement
'//Declares the connection using Persist Security Info=false
sConnectionString = "Provider=SQLOLEDB;Data Source=localhost; User ID=acdev;” & _
“Password=acdev; Initial Catalog=Keyadmin40; Persist Security Info=false;"
adoConn.Open (sConnectionString)
pwd = adoConn.Properties("password") '//pwd is blank, this is ok
MsgBox adoConn.ConnectionString '//password text is not shown, this is ok
rstConsulta.Open sSql, adoConn '//Executes ok
adoConn.Close '//Closes connection
‘//If the next line is uncommented, the message box will not show the password text.
‘//pwd = adoConn.Properties("password") '//pwd is blank, this is ok
MsgBox adoConn.ConnectionString ‘// The password text is shown, which is really bad.
Set adoConn = Nothing
Exit Sub
ErrorHandler:
'//If an error occurs, for example the table name on the sSql string
'//does not exist
MsgBox Err.Description
MsgBox adoConn.ConnectionString '//password text is not shown, this is ok
adoConn.Close
MsgBox adoConn.ConnectionString '//password text is SHOWN, this is really bad
End Sub
Conclusion:
Password text is shown after the data source object has been uninitialized
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Where does it say that the password is not shown in the connection string after the connection has been closed?
Documentation only talks about the Properties collection, not the ConnectionString.
I'd say the class behaves as specified and documented...
mav
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Im trying to add an expresion which adds a value to the column records
something like this:
datacolumn1.Expresion = datacolumn1 + 10;
and i get an exception ,how can i do this?
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Use like this.
dataColumn1.Expression = "datacolumn1name + 10"
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this is what i ment , and it doesnt work if the columnname is the same as the column you give the expresion to.
this is the exception i get : Cannot set Expression property due to circular reference in the expression.
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I'm trying to connect to DB from Java, I'm doing it exactly like in The Java Tutorial and I'm getting this exception:
"java.sql.SQLException: [Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified"
What does it mean, and what's with the "default driver"?? There isn't anything about drivers in that tutorial... :/ And about that strange url strings neither... :/
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I have a function in an SDI MFC (no .NET) application that needs to return data in an ADO Recordset. There is no database involved. I simply want to use the ADODB::_RecordsetPtr type as my return type.
How can I create the recordset without a database, connection, session, etc?
Thank you for your support.
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See the ADO wrapper library here.[^]
Use the parameterless constructor to create the recordset. Use AppendField to puplulate the columns, then OpenDisconnected to open it for adding rows, etc. You will likely need to add a function to clone and return the member m_pRecordset (_Recordset*), but the existing Clone function should show the way...
Power corrupts and PowerPoint corrupts absolutely. - Vint Cerf
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Rob Graham wrote:
See the ADO wrapper library here.[^]
Thanks for the suggestion. However, I can't afford to add the overhead of this project just to get a recordset.
All I'm looking for is a way to create a recordset without a connection, session, etc. This must be a simple thing for someone who works with ADO everyday, but it is a puzzle for me!
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First, it's not that much overhead.
second, you could just examine the source and look at the functions i mentioned to see how they are imlemented. The OpenDisconnected does just what you are looking for.
If you dont wan/need the whole libratry, just copy the couple of functions you need into a trimmed-down class...
Power corrupts and PowerPoint corrupts absolutely. - Vint Cerf
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Dear All,
I want to make a simple application that will work like a personal diary. To accomplish that I need to store an image (may be a gif or bmp) in a sql db table. plz guide how to do this?
Thanks
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refer
http://www.dotnetspider.com/Technology/KBPages/558.aspx
Sanjay Sansanwal
www.sansanwal.com
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I want to develope a small db app in vc++6. My only requirement is that my users not have to install anything other than my app (and maybe a later version of mdac).
Is ADO okay for this?
Can someone recommend a good book about it?
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check
http://www.samspublishing.com/title/0672312409
Sanjay Sansanwal
www.sansanwal.com
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Hi, I have a SQL database with usernames and passwords.
1)Now I need find a user name (which user wrote into textbox) and prove the password.
2)I have a registration page, it works well, but I would like to search the database before I add the new record to it, (no duplicity)
3)How can I delete a record? (update record)
Thanks very much for your answer
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None of these questions can be answered without knowing the schema of your database, you should be able to answer them all from the books online, and this smells like homework
Christian
I have drunk the cool-aid and found it wan and bitter. - Chris Maunder
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1. For security you should always store the passwords in an encrypted form. When the user registers for the first type encrypt the password. When the user logs in on subsequent sessions encrypt the password again and search for the encrypted version of the password.
SELECT COUNT(*) FROM myRegistrationTable WHERE UserName=@userName AND EncryptedPassword=@encryptedPassword The above code will return 0 if the user name and password cannot be found, or 1 otherwise. If it returns any other value the database contains duplicate information.
2. You can apply a unique constraint to the table to ensure that no duplicates are entered. Also the primary key is by default a unique value - so sufficient uniqueness may already be covered. If you do this SQL Server will raise an error when you perform your insert and you can pick this up in your .NET application by catching the SqlException that is generated.
You could also write a stored procedure that checks for the existance of a record first then conditionally inserts the new record if there isn't one already.
3. Use the DELETE command.
Does this help?
"If a man empties his purse into his head, no man can take it away from him, for an investment in knowledge pays the best interest." -- Joseph E. O'Donnell
Can't manage to P/Invoke that Win32 API in .NET? Why not do interop the wiki way!
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