Retrieving available OLEDB Providers and settings programmatically

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  - 1
    - OleDb DataAdapter Fill puzzle Hi, Working with ADO.Net/OleDb and Access2000. Using dataAdapter1 to update Access table field and dataAdapter2 to display the value from the same Access data source. Problem is, although dataAdapter1 is updating the Access table (verified in Access), subsequent calls to the dataAdapter2 Fill method do not refresh from the Access source - the value coming out of the dataAdapter2 dataset is always the same value - the one initially read on application startup. According to the documentation the Fill method should refresh the dataset from the data source - but does it? Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64323
  - 2
    - Passing datetime as parameter throws Exception I have data field MyTime of type Date/Time in MS Access table Test. I want to add record into this table with value passed as parameter. I do the following in C#: OleDbCommand cmd = new OleDbCommand(); cmd.Connection = MyConnection; cmd.CommandText = "INSERT INTO Test (MyTime) VALUES(?);"; cmd.Parameters.Add("MyTime", DateTime.Now); cmd.ExecuteNonQuery(); Last statement throws an exception with message "Data type mismatch in criteria expression." If I pass only date part to parameter, for example: cmd.Parameters.Add("MyTime", DateTime.Today); it works fine. How can I create and use parameter that wold pass both date and time parts to date/time field? Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64321
  - 3
    - ADO.NET Performance Tuning Hello, I have used ADO.NET to retrieve records (about 700 rows) from SQL2000 server and found that the performance (speed) is not good as ADO object. (Same Select statement applied) I would like to askwhat setting, in the DB side or client sides,I should aware so that I can improve the performance? Thanks Douglas Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64309
  - 4
    - MSDE in install Hi How to include MSDE into install and during install create some tables so program and database server are ready to work? Thanks Konrad Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64308
  - 5
    - GetXML doesn't show Computed Columns Anyone know if this is the way this is supposed to be working or any potential workarounds? I have a DateTime column 'DateExpires' which I am returning as a computed column via my SELECT statement. When I call GetXML() on the DataSet, it isn't returning the computed column. However, when I do a quickwatch on the DS, I see that the column is in the dataset. Also, I have a bound webform control which is getting populated with the value from this column in the dataset. strCmd = "SELECT ID, CAST((DATEPART(m, DateExpires)) as varchar(2))+ '/' + CAST((DATEPART(d, DateExpires)) as varchar(2))+ '/' + CAST((DATEPART(yy, DateExpires)) as varchar(4)) as DateExpires FROM Articles" sqlDA.SelectCommand = new SqlCommand(strCmd, sqlCN); sqlDA.Fill(objDS); objDS.GetXML() returns: <DSArticles xmlns="http://tempuri.org/Schema_Articles.xsd" /> <NewDataSet> <Articles> <ID>e75baa38-f084-472e-a14f-2517f00f3d67</ID> </Articles> </NewDataSet> XSD as follows: <?xml version="1.0" encoding="utf-8"?> <xs:schema id="Schema_Articles" targetNamespace="http://tempuri.org/Schema_Articles.xsd" elementFormDefault="qualified" xmlns="http://tempuri.org/Schema_Articles.xsd" xmlns:mstns="http://tempuri.org/Schema_Articles.xsd" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata"> <xs:element name="Document"> <xs:complexType> <xs:choice maxOccurs="unbounded"> <xs:element name="Articles"> <xs:complexType> <xs:sequence> <xs:element name="ID" msdata:DataType="System.Guid, mscorlib, Version=1.0.3300.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" type="xs:string" /> <xs:element name="DateExpires" type="xs:string" minOccurs="0" /> </xs:sequence> </xs:complexType> </xs:element> </xs:choice> </xs:complexType> <xs:unique name="DocumentKey1" msdata:PrimaryKey="true"> <xs:selector xpath=".//mstns:Articles" /> <xs:field xpath="mstns:ID" /> </xs:unique> </xs:element> </xs:schema> Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64303
  - 6
    - ANN: September 2, "ADO.NET with Visual Basic .NET"" chat Every application uses data. Come and ask members of the Visual Studio and SQL teams about the best approaches for working with data in your applications. Date: September 2, 2003 Time: 1:00 - 2:00 P.M. Pacific time 4:00 - 5:00 P.M. Eastern time 20:00 - 21:00 GMT 21:00 - 22:00 BST (For a list of local time zones relative to GMT, please see http://msdn.microsoft.com/chats/timezones.asp.) Location: http://msdn.microsoft.com/chats (then click the name of the chat to enter the chat room) To see a list of upcoming chats or set a reminder for this chat, please see http://msdn.microsoft.com/chats. You can use the following link to add an event reminder to your calendar for this chat. http://msdn.microsoft.com/chats/outlook_reminders/VB_Sept2.vcs To see an archive of previous chat transcripts, please see http://msdn.microsoft.com/chats/recent.asp. Thanks! Jason Cooke VB.NET Team ======== This posting is provided "AS IS" with no warranties, and confers no rights. You assume all risk for your use. (c) 2003 Microsoft Corporation. All rights reserved. Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64301
  - 7
    - network packet size I recently switched my production db from one server to another. My app connects with this connection string ("data source=servername;initial catalog=dbname;integrated security=SSPI;packet size=8192") to the old server fine, but will not connect to the new server unless I decrease the packet size from 8192 to 4096. I ran sp_config on both machines and the network packet size is the same for each server. Any ideas or areas I could check? I guess it's not that big of a problem, but I would like to know why. Thanks Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64291
  - 8
    - DataRowChangeEventHandler Issue I have written a DataRowChangeEventHandler to act as a "security" filter based on the current users "role". The event handler needs to be able to reject/cancel Inserts to the ADO.NET DataTable (these inserts are the results of a Select against the dataSource using the Fill method on a SqlDataAdapter). I've tried throwing an exception inside the handler, which doesn't appear to do anything. I've also tried calling RejectChanges on the row. This seems to work, but also seems to leave an invalid row in the table in a "Detached" state, which causes things like AcceptChanges to blow up later on. I suspect I'm just going about this the wrong way, but haven't seen an example anywhere of how to prevent a Row from being added to a DataTable. My code is shown below -- does anyone know what the "right" way is to do this? Thanks in advance, Jeff private void FrameworkRowAddedSecurityMonitor(object sender, IFrameworkTableSecurityEvent e) { if (e.Action == DataRowAction.Add) { if (e.SecurityObject.DataType != null) { if ((e.SecurityObject.AccessMask & ContentManager.FW_ACL_PERMISSION_READ) == 0) { // Option 1 DataRow row = (DataRow) e.SecurityObject; row.RejectChanges(); // Option 2 throw (new ContentManagerSecurityException("Access Denied",e.SecurityObject,ContentManager.FW_ACL_PERMISSION_R EAD,e.SecurityObject.AccessMask)); } } } } Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64288
  - 9
    - Oracle CLOB parameter limit? Hey all, I'm getting the following error when calling an Oracle9i proc from a .net 1.1 app, passing a clob parameter that is larger than ~32,000 characters: ORA-01460: unimplemented or unreasonable conversion requested. Is there a parameter size restriction for oracle procs? How do I pass in a large clob to the database? I'm using the MS managed provider for oracle, and the oracle9i drivers.... TIA, Andrew Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64287
  - 10
    - Cannot execute DTS package from ASP.Net Hello: I've got another problem executing DTS package from ASP.Net. I use this code: Dim oPkg As DTS.Package oPkg = CreateObject("DTS.Package") oPkg.LoadFromSQLServer("WIN2000", "UID", "password", DTS.DTSSQLServerStorageFlags.DTSSQLStgFlag_Default, , , , "Import_Sales_History") oPkg.Execute() oPkg.UnInitialize() oPkg = Nothing I used this code before, and it always worked. Now it doesn't. The problem is that I'm not receiving any error messages, so I cannot find out what's wrong. When I step through the code I don't see anything unusual. But in fact it doesn't do anything, no data has been imported. When I execute the package manually - everything is OK. What could be a problem? I would appreciate your help. Thank you, -- Peter Afonin Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64285
  - 11
    - Problem updating existing typed dataset from Generate Dataset designer Hi, I'm trying to update an existing Typed dataset in a VB Web project using the "Generate Dataset" designer from a SqlDataAdapter. When I try to add new tables or updated fields, the wizard closes like it does for a new typed dataset, but the selected dataset schema does not change. What I've been doing as a workaround is to just delete the existing ds and creating a new one with the same name. Is there a fix out there or do I just have something setup wrong? I'm using: Visual Studio 2002 VB - Web forms SqlDataAdapters - SQL Server 2000 .NET Framework 1.0 Thanks in advance, Eric Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64278
  - 12
    - Change Winform Query Question I had an experience this morning that I don't quite understand with VS 2003. I have a Winform with the underlying data coming from three different tables. This data for the Winform is obtained by use of a dataset. The form has tabs. Data in the Contracts table goes to the Contracts tab, data in the Students tables goes to the Students tab etc. For each of these tables I have a SQLDataAdapter in the component tray of the Winform. DaContracts, DaStudents, & DaArd. When I generate a Dataset for each of these 3 data adapters I point to a DataSet I call DSMain (DsMain1). That is, DSMain has schema involving all there of these tables and they are (in the schema) related together in the proper way and in the same way they are related in the underlying SQL 2000 tables. Sorry to be too wordy. Don't know how to explain the problem, however, without saying at least that much. It was necessary for me to add some fields to the main table (contracts). These fields were not selected in the original query that produced the contracts table in the DataSet Schema. I added the fields in the query of the DaContracts DataAdapter and re-generated the dataset for that adapter. I then tried to run the form and got back an error message of "Could not create a child list for fields DrContractsArd". This is the data relations name for the Contracts and Ard tables. I horsed around with it and finnaly got the form back up and running as before but for future reference, I would like to understand what happend. I think the moral of the story is that if you add fields or change things in the future with regard to one table in a dataset involving more than one table, it is not enough to re-generate the dataset for just that table, you must regenerate the dataset for all the tables. Is this right or are there other comments or items that others would like to bring to my attention? I am new to VS and may have made an incorrect assumption in tying these three tables together in one dataset. Maybe each table should have a dataset of it's own. I don't know. I did it this way in the first place for reasons I don't remember other than, it worked. Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64263
  - 13
    - Cannot delete last row in a datagrid Hi all. I have a datagrid bound to a dataset/datatable. Obviously I created a BindingManager and a CommandBuilder and all runs well when I ADD new rows or DELETE existent rows, saving all back to the database. Here is the code associated to a button, I use for "deleting" a row: ---------------------------------------------------- Dim dr As DataRow dr = ds.Tables("checkout").Rows(bm.Position) dr.Delete() MsgBox(ds.Tables("checkout").Rows(bm.Position).RowState) If ds.Tables("checkout").Rows(bm.Position).RowState = DataRowState.Deleted Then MsgBox("row deleted") da.Update(ds, "checkout") End If ------------------------------------------------------ As you can see I found the row first and the "delete" it (the RowState is only for debugging purpose :-) Well I CAN delete all rows in the datagrid (clicking on the row and then clicking on the Delete Button), obtaining a DataRowState.Deleted value (as expected). But the problem is when I try to delete the last row in the grid: the row is deleted from the grid, but no changes are made to the RowState (obtaining a Unchanged value). So no Update is possibile on that row. I can't understand why! Have you any idea? Many thanks. -- Francesco De Carlo Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64259
  - 14
    - Lhotka's VB.Net Business Objects Has anyone tried implementing Rockford Lhotka's CSLA framework from his book Expert One on One Visual Basic .Net Business Objects? The reason I pose this question here is 2-fold. 1. He basically does away with most of ADO.net, other than the DataReader to read a row in order to stuff the values into Properties of objects, which are then bound to UI controls. To update the database, the values from the Properties are used to generate a SQL update statement. It certainly seems an odd way of doing things - albeit in an OOP way. 2. Having spent 3 weeks trying to work through the book and make it work, I can't seem to be getting anywhere. His downloaded source code refuses to work - even after some of the more obvious problems are fixed (like references to a Strongname Key file stored on his own h:\ drive in some of the Assembly Info files). The sample Project Tracker keeps quiting with a System error. I am very intrigued with his framework, and I think Mr Lhotka is one of the best technical writers around. I find myself stuck in the mud and would like to know if anyone out there has been able to make this thing work. Thanks Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64256
  - 15
    - Class Reference Sorry for crossposting! Is there a complete reference of .NET Framework class libraries? And i mean COMPLETE reference with full explanation of what each class does and perhaps what it's good for. Reason for this is that recently i spent 2.5 days coding a class only to find out that Framework already supplied me with a similar class (the same functionality), only i never knew about it :-( So i would like to know when i must code my own functionality solutions and when there's something in .NET that i can use. Btw don't point me to MSDN cause i have latest library and i'm aware of the library online, but they only give a very little information about classes in Framework, and almost no examples. Thanx in advance Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64243
  - 16
    - Urgent Help Needed !! FTP Files from Webserver to Client PC Hello, I need to download files from the web server to the PCs without the "Save As" Dialog Box using ASP.NET . Pls advise if there are any components available for any help is appreciated. Thank You EJ Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64237
  - 17
    - DB optimisation vs OOP layer separation Hi, I'm facing a code-optimisation issue on an asp.net/vb.net/SQL Server 2000 project. A web page containing not much more than 3 DropDownLists is taking nigh on 6 seconds to load, because each ddl opens up a separate connection to the DB, pulls out its data, and closes its own connection before the next ddl repeats the process. The code to handle each DDL's connection to the DB is packaged in an object (presentation-layer code below); two of the hits go via a Person object, and one via a User object. Both these objects are separated into a business layer and a data layer. My optimisation goal is to have all these three DB hits done on just one DB connection. The only way I can think of doing this would be: * create a connection object in the presentation layer (more likely, an SqlCommand object which contains an open connection), * pass this open connection to Person.GetAllActiveNonIntroducersOrderBy("LastName", "ASC") * the presentation layer gets the open connection back from Person.GetAllActiveNonIntroducersOrderBy("LastName", "ASC"), laden with data * the pres layer takes out the data, fills up DDL1 with it, and passes the still-open-connection to Wec.User.GetAllOrderBy("LastName", "DESC") * the open connection comes back once more to the presentation layer, laden with the second batch of data * DDL2 is filled up with this data, and the process repeats for DDL3 * once the pres layer has got all the necessary data it kills the connection I dare say I could adapt the various Business and Data Layer routines to handle this. My main worry is about violating the OOP principle of layer separation - if I'm going to start creating SqlConnections / SqlCommands in my *presentation layer*, I might as well slit my OOP wrists right now.... Any input welcome! TIA, JON 'DDL1 ddlIntroducerNames.DataSource = Person.GetAllActiveNonIntroducersOrderBy("LastName", "ASC") ddlIntroducerNames.DataTextField = "WholeName" ddlIntroducerNames.DataValueField = "PersonID" ddlIntroducerNames.DataBind() 'DDL2 ddlWECReps.DataSource = Wec.User.GetAllOrderBy("LastName", "DESC") ddlWECReps.DataTextField = "WholeName" ddlWECReps.DataValueField = "UserID" ddlWECReps.DataBind() 'DDL3 ddlIntroducedBy.DataSource = Person.GetAllActivesOrderBy("LastName", "ASC") ddlIntroducedBy.DataTextField = "WholeName" ddlIntroducedBy.DataValueField = "PersonID" ddlIntroducedBy.DataBind() Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64232
  - 18
    - How do I insert into an Excel spreadsheet? I am using Excel as a small database to store settings of a comm program I am writing. While I can read from excel fine, I am stuck on how to write any changes back to the database. I have been trying to use an INSERT INTO but I get the following error: Operation must use an updateable query I am really new with using ADO.Net and this is my first application trying to use Excel as a datasource. Any guidance or suggestions on how to go about fixing my error would be appreciated. The code I am using is as follows: 'clear the dataset dsSettings.Tables("Settings").Clear() 'insert a new row into the datatable Dim dtSettings As DataTable = dsSettings.Tables("Settings") Dim drNewRow As DataRow = dtSettings.NewRow drNewRow.Item("Baudrate") = sBaudRate drNewRow.Item("Parity") = sParity drNewRow.Item("Handshake") = sHandShake drNewRow.Item("Databits") = sDataBits drNewRow.Item("Stopbits") = sStopBits 'add new row to Settings table dtSettings.Rows.Add(drNewRow) Dim sSQL As String sSQL = "INSERT INTO [Settings$] " sSQL = sSQL & "(Baudrate," sSQL = sSQL & "Parity," sSQL = sSQL & "Handshake," sSQL = sSQL & "Databits," sSQL = sSQL & "Stopbits) " sSQL = sSQL & "VALUES (" sSQL = sSQL & "@Baudrate," sSQL = sSQL & "@Parity," sSQL = sSQL & "@Handshake," sSQL = sSQL & "@Databits," sSQL = sSQL & "@Stopbits)" Dim mExcelConnection As OleDb.OleDbConnection = New OleDb.OleDbConnection mExcelConnection.ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & sAppPath & "Settings.xls;Extended Properties=""Excel 8.0;HDR=Yes;IMEX=1""" Dim mExcelAdapter As OleDb.OleDbDataAdapter = New OleDb.OleDbDataAdapter mExcelAdapter.InsertCommand = New OleDb.OleDbCommand(sSQL, mExcelConnection) mExcelAdapter.InsertCommand.Parameters.Add("@Baudrate", System.Data.OleDb.OleDbType.VarChar, 10, "Baudrate") mExcelAdapter.InsertCommand.Parameters.Add("@Parity", System.Data.OleDb.OleDbType.VarChar, 10, "Parity") mExcelAdapter.InsertCommand.Parameters.Add("@Handshake", System.Data.OleDb.OleDbType.VarChar, 10, "Handshake") mExcelAdapter.InsertCommand.Parameters.Add("@Databits", System.Data.OleDb.OleDbType.VarChar, 10, "Databits") mExcelAdapter.InsertCommand.Parameters.Add("@Stopbits", System.Data.OleDb.OleDbType.VarChar, 10, "Stopbits") mExcelConnection.Open() mExcelAdapter.Update(dsSettings, "Settings") mExcelConnection.Close() Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64226
  - 19
    - MS Oracle ADO.NET provider bug 2? The following code returns an InvalidOperationException syntax error when stepping over the da.FillSchema statement : Syntax Error: Expecting ',' or 'FROM' after column alias or '*'. The same code works fine using either the MS OleDb data provider or Oracle's native provider. If I add parentheses around BUDGET*5, then the code executes as expected. string connStr = "Data Source=myserv;User ID=scott;Password=tiger;"; OracleConnection conn = new System.Data.OracleClient.OracleConnection(connStr); string sql = "SELECT BUDGET*5 FROM PROJ WHERE PNUM='P1'"; OracleCommand cmd = new OracleCommand(sql); cmd.Connection = conn; conn.Open(); try { DataSet ds = new DataSet(); OracleDataAdapter da = new OracleDataAdapter(sql, conn); da.SelectCommand = cmd; da.FillSchema(ds, SchemaType.Source); ds.EnforceConstraints = false; da.Fill(ds); } catch (Exception Ex) { MessageBox.Show(Ex.Message); } conn.Close(); Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64216
  - 20
    - OleDb .NET provider bug with Oracle? I appear to have hit a couple of bugs in the OleDb .NET data provider, working with Oracle 9.2.0 on a Windows 2000 client. I'm not sure whether this is the correct forum to report this? Whitespace after the DISTINCT clause appears to get ignored, causing an exception. With the code below, on stepping over the da.fill statement, I get this exception error: ORA-00904: "DISTINCTcol1": invalid identifier Using the Microsoft ADO.NET provider for Oracle (or Oracle's native provider), the SQL statement is executed correctly. I'm not sure if this has been reported before. Is there a fix available to correct this? Simon. string connStr = "Provider=OraOLEDB.Oracle.1;Persist Security Info=False;Data Source=myserv;User Id=scott;Password=tiger;"; OleDbConnection conn = new OleDbConnection(connStr); string sql = "SELECT SUM(DISTINCT col1) FROM mytable"; OleDbCommand cmd = new OleDbCommand(sql); cmd.Connection = conn; conn.Open(); try { DataSet ds = new DataSet(); OleDbDataAdapter da = new OleDbDataAdapter(sql, conn); da.SelectCommand = cmd; da.FillSchema(ds, SchemaType.Source); ds.EnforceConstraints = false; da.Fill(ds); } catch (Exception Ex) { MessageBox.Show(Ex.Message); } conn.Close(); Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64210
  - 21
    - file download - using response.writefile() Hi, I have ASP.NET page that would like to download a list (many) pdf files. I intend to down the file into the browser C:\ root drive without prompting the user to "SAVE AS" dialog box. Would appreciate some help on this (maybe a code snipnet). Thanks EJ Chew Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64205
  - 22
    - DataRepeater for windows forms Hi, I've sen that VB6 has a datarepeater and that ASP.NET has something like that. But is there something like that for windows forms, or has someone something like that? Thanks Filip Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64204
  - 23
    - ADO.NET in C# - statement problem, please help? I've been stuck with this stupid problem for the past two days.. I give up now, please help me? Here's the code : OleDbCommand updatedb = conn.CreateCommand(); updatedb.CommandText = "INSERT INTO maintable (name, number) VALUES ('John Smith', '01215489746')"; updatedb.ExecuteNonQuery(); When I release/debug my app in VS.NET I get a succeeded build. However when I want to run the app I get on the screen : " OleDbException : Syntax Error in INSERT INTO statement. " Obviously there's something wrong with the SQL command I'm writing, but what? I really don't get it and I've honestly tried everything. For the info, I'm trying to connect to an Access DB. Please share you knowledge with me.. thanks so much! By the way, if anyone's got a good website with an ADO.NET tutorial (for beginners:P) please let me know.. thanks jez Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64200
  - 24
    - datareaders and GetDirectory() Hi all, in my quest to implement my own data reader, i've been delving deeper into the inner workings of data readers and am now stuck on the GetDirectory() method. I know that this method is an internal method of the data reader class. It takes a string that is used to create a new DirectoryInfo object: internal void GetDirectory(String command) { _dir = new DirectoryInfo(command); _fsi = _dir.GetFileSystemInfos(); _RecordsAffected = _fsi.Length; _CurrentRow = -1; _ie = _fsi.GetEnumerator(); _isClosed = false; } I also know that it is used when ExecuteNonQuery() or ExecuteReader() are called. When either of these methods are called this is what happens (as i understand it): a DataReader is instantiated, its internal GetDirectory() method is called which returns either: - the number of directory entries returned (i.e. the number of rows affected) - or a DataReader over the set of entries (by getting an enumerator over the directory entries) The code above seems to suggest the CommandText of the Command being executed is passed to GetDirectory(). But the constructor for DirectoryInfo expects a string that represents the path of a directory. This is where i'm stuck...what should be passed to GetDirectory()? The code above and the sketchy info i possess on all of this was gleaned from : http://msdn.microsoft.com/msdnmag/issues/01/12/dataprov/ (Under the "Implementing DataReader" section. The code is part of Figure 8.) Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64196
  - 25
    - [Q] Reading BOOLEAN return value from Oracle function Hello, Can anyone tell me how to retrieve a boolean return value from an Oracle Function, using MS .Net Framework Data Provider for Oracle? In the documentation there's a "Mapping Data Types" table that shows which Oracle data types correspond to which .Net types (OracleType.xxx), but Boolean is omitted... My code is like this: ... other parameters... oracleCommand.Parameters.Add("O_retval",OracleType.XXXXX).Direction = ParameterDirection.ReturnValue; .... what do use in place of the XXXXX when the Oracle function returns a BOOLEAN? Any help would be greatly apreciated. Thanks in advance, Joao Martins -- João Pedro Martins jota@create.pt www.create.pt www.usabilidade.com Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64186
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  - 1
    - Trusted connection doesn't work with SQL server and ASP.Net Hello: I need to execute a DTS package from an ASP.Net application. The SQL server registration properties are set to "Use Windows authentication". domain\ASPNET is among the SQL server users. However, when I use this string to load DTS package: oPkg.LoadFromSQLServer("WIN2000", , , DTS.DTSSQLServerStorageFlags.DTSSQLStgFlag_UseTrustedConnection, , , , "Import_Sales_History") I get this error: "System.Runtime.InteropServices.COMException (0x80004005): Login failed for user '(null)'. Reason: Not associated with a trusted SQL Server connection. at DTS._Package.LoadFromSQLServer(String ServerName, String ServerUserName, String ServerPassword, DTSSQLServerStorageFlags Flags, String PackagePassword, String PackageGuid, String PackageVersionGuid, String PackageName, Object& pVarPersistStgOfHost) If I specify UID and password: oPkg.LoadFromSQLServer("WIN2000", "UID", "password", DTS.DTSSQLServerStorageFlags.DTSSQLStgFlag_Default, , , , "Import_Sales_History") everything works OK. Why the trusted connection doesn't work in my case, despite that the SQL server properties are set to use it? I would appreciate your help. Thank you, -- Peter Afonin Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64184
  - 2
    - SQL Indexes I have a question regarding indexes. This may be a SQL newsgroup question. If it is I apologize. I actually posted it on both just in case. If I create an index on a table. Will this index be checked through when I execute a select statement from VB.NET or is this index only used through strored procs within sql. Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64182
  - 3
    - Saving Times in .Net I'm trying to save a time (08:01 for example) to a Data/Time field (formatted Short Time) in an Access table using VB.NET. The problem is that even when I write this time to a dataset, it winds up saving as #08/28/2003 08:01 AM# in the database, where the date is today's date. In plain ol' VB6, I am able to write 08:01 to the database with no date. Is there any way to write the time only in VB.NET? Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64178
  - 4
    - Sorting Datatable I have a datatable in which the adapter has not been updated (and I dont intend to) and I want to stop after adding the rows to the datatable and sort them by lets say the SLSM column DESC. Usually I would when calling data sorted in a SQL server table would use a select statement but how would I do this when all it is is a dataset with all the rows added? If I have to I will update the data adapter and add all the rows to the datatable but I would rather not do that if I do not have to. Thanks for your help...... Me.Dshistory1.HISTORY.Rows.Add(drnew)'row dshistory1.acceptchanges End If Loop 'now sort this dataset(datatable) as I get ready to do actions Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64169
  - 5
    - TSEQUAL doesn't work with ADO? Hi all, I use the TSEQUAL function to check the equality of timestamp columns to perform optimistic concurrency. I know TSEQUAL is undocumented, but it usually works well. Unfortunately, when I use sps that use TSEQUAL, they do not throw errors when the timestamp values are different. Instead, it simply writes over the existing row. I have verified that TSEQUAL works correctly within the sp by running tests in Query Analyzer. The only difference between my test scenario and live scenario is that in the live scenario the two updates take place on different connections. I made sure ,however, that the changes were commited before attempting to update from another connection. Does anyone have any experience with this? Cole Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64167
  - 6
    - Using ADO.NET to connect to a CSV File, Need Help Using an ODBCConnection and ODBCDataAdapter object, I am able to connect to a CSV file. However, my data tables are all comeing back with the first line of the CSV file used as a column header line. How do i disable this? TIA// Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64166
  - 7
    - Ambiguous ConstraintException I am doing a pretty basic Fill() call to a SqlDataAdapter filling a DataTable. The Fill() call throws a ConstraintException, but the message is extremely ambiguous. I get the ever-cryptic message, "Failed to enable constraints. One or more rows contain values violating non-null, unique, or foreign-key constraints." Does anyone know where to begin debugging such a problem with over 300 columns? I wish it would provide more useful information such as which constraint and what value violated it. Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64160
  - 8
    - Why doesn't GetColumnError or GetColumnsInError return anything when the dataset HasErrors? If I do the following code I get nothing returned. Dim i As Integer For i = 0 To ds.Tables(0).Columns.Count - 1 If ds.Tables(0).Rows(0).HasErrors Then MsgBox(ds.Tables(0).Rows(0).GetColumnError(i)) End If Next I get a message box for every column and message boxes are always blank. Why? Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64158
  - 9
    - populate a treeview from a db I'm trying to populate a treeview from a SQL tables in C#. i've written the SQL procedures (i.e. database wise is sorted). However, I would like to see an example of how to retrieve the data from the tables (recrusive method). I finally worked out how to retrieve the data. it was just a matter of understanding the database class I am using. However, one problem I have at the moment is that I could display the parent nodes and the first node subnodes which is not even what I want to display (i need to modify the procedure). the following is the method I created to display the data from the table. any idea how I could display subnodes (i.e. code logic!) //------------------------------------------------ private void buildTreeView() { // the connection string and command string // "upDisplaySites" is the SQL Procedure name ..... string connstring = ConfigurationSettings.AppSettings["ConnectionString"]; DataTable dt = TMG.Data.DataAccess.GetResultTable("upDisplaySites", connstring); DataTable dt1 = TMG.Data.DataAccess.GetResultTable("upDisplayGroups", connstring); DataTable dt2 = TMG.Data.DataAccess.GetResultTable("upDisplayUsers", connstring); treeView1.Nodes.Clear(); try { TreeNode parentNode = new TreeNode(); foreach(DataRow dr in dt.Rows) { treeView1.Nodes.Add(dr["Name"].ToString()); //TreeNode tNode = new TreeNode(); parentNode = treeView1.Nodes[0]; } // this needs to be changed! foreach(DataRow dr1 in dt1.Rows) { TreeNode subNode = new TreeNode(); parentNode.Nodes.Add(dr1["Name"].ToString()); subNode = treeView1.Nodes[0]; } } catch (Exception ex){ MessageBox.Show("Err");} } } //-------------------------------------------------------------------------------------- the above displayed the Sites as follows: ============== -a -1 -2 -3 -b -c -d -f ============== The idea is to display the sites then the groups within the sites and then the users in each group. (i.e. 3 levels of nodes) Any idea of I could logically work this out. (note: the table are as follows: site, group, user and others involved. i.e. multiple table are used) Thank you in advance. Kam Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64157
  - 10
    - Does anybody have any idea what this message means? "The data value could not be converted for reasons other than sign mismatch or data overflow. For example, the data was corrupted in the data store but the row was still retrievable." I can't find this anywhere in MSDN, and the google search I did didn't return anything useable. I am useing and OleDb dataAdapter to update a table in a Sybase ASA database. I have another adapter that does a similar action on another table and it works fine. There are only two minor wrinkles in what I'm doing, and I don't think they are having any impact: 1) I am updateing based on the primary key for the table (call this Column A), however my select command retrieves based on an foreign key (Column B). I am not updating either of these columns. 2)I am using a stored procedure with a bit and a long varchar argument, amoung three others which are varchar and an int which is the primary key. I tried taking the bit and long varchar out and got the same error. The only other thing I can say is that the code is exactally what the "wizard" created, so I doubt it's a typo or anything. Thanks, James Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64134
  - 11
    - how to create/populate strongly typed dataset from data in a listview I am trying to populate a strongly typed dataset from data that is residing in a list view. Any hints or suggestions would be appreciated. Thanks. I guess i should mention this is in vb .net thanks. Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64131
  - 12
    - Datagrid Navigation event again Here is the scenario: I have a hierarchical data grid. I click on expansion sign on row (this row is not the currently selected row) and then navigate to show the detals of that row. Now is there a way to get the row on which I clicked to navigate to the child-rows? Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64127
  - 13
    - HELP: Recordcount always -1 (using adOpenKeyset) I cannot get my recordcount to show up properly (using ADO 2.5). It keeps showing -1! Here's a snippet: Dim dbMyDb As New ADODB.Connection Dim rsWebData As New ADODB.Recordset dbMyDb.Open gConnectionString rsWebData.Open "SELECT * FROM WebDataLogAc;", dbMyDb, adOpenKeyset, adLockOptimistic rsWebData.MoveFirst Debug.Print rsWebData.RecordCount This always returns -1 even though there are records in the table. HELP!!! Thanks! Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64125
  - 14
    - collections / OO approach on datasets Hi! I was wondering if there is a "better" way to use dataset's instead of using "someset.Tables["sometable"].Rows[index][index]" in order to get the content out of the datatables. I think "collections" is what I'm looking for, though I'm really not sure. I have a dataset that has 8 tables in it. If I used collections or something, then I could make it a little easier to work on, so that I didn't have to keep track of coloumn names everytime I need to use the dataset somewhere. It would be great if anyone has some URL's or examples I could look at, on how to create collections from a dataset. C.H Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64124
  - 15
    - Navigate event of datagrid How can I get the parent row information of row that I am going to be in, when I navigate to a child table within a hirarchical datagrid? Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64119
  - 16
    - is ADO.net built on top of ADO? Is this statement true? "ADO.NET doesn't have it's own engine to connect to a data source, it uses ADO internally. It's another layer on top of ADO. It's pretty much the same as doing an interop with the ADO components... " Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64114
  - 17
    - OracleDataAdapter I am using OracleDataAdapter.FillSchema() to get the primary key information for the table used in the query string assigned to the command. If the table is referenced directly (such as SELECT * FROM SCHEMA.TABLE) I get the array of DataColumns in the primary key. If the table is referenced through synonyms (public or private, such as SELECT * FROM TABLE where the table is in a different schema) I get no primary key columns. .NET Framework 1.0.3705 Microsoft Oracle .NET Data Provider 1.0.0.3328 Using a later version of the .NET Framework is not an option. Thanks. Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64111
  - 18
    - Update problems on Parent-Child relation SQL Server 2000, Visual C# 2003, NET Framework 1.1 I add one row of data to parent table and some rows of data to child table. When I send updates to server only parent row updates but child rows doesn't. I count number of added child rows (with DataViewRowState.Added) before update parent table and I see correct counts. After update parent table, and before update child table, I count again number of added child rows but this time I see zero records. MessageBox.Show(dsUsers.UsersRights.Select("","",DataViewRowState.Added).ToS tring()); -return 2 records. MessageBox.Show(sqlDaUsers.Update(dsUsers,"Users").ToString()); - return 1 record. MessageBox.Show(dsUsers.UsersRights.Select("","",DataViewRowState.Added).ToS tring()); - return 0 records. MessageBox.Show(sqlDaUsersRights.Update(dsUsers,"UsersRights").ToString()); - don't work, no error messages but no updates. I try even this: 1. Submit new parent rows 2. Submit new child rows 3. Submit modified parent rows 4. Submit modified child rows 5. Submit deleted child rows 6. Submit deleted parent rows but the same results. On the server relation between parent and child is cascaded for update and delete. Where is my mistake ? Dan Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64107
  - 19
    - datatable doesn't see modified rows Hi, I'm binding a DataTable to several controls and everything seems to be reflected okay. When comes to updating the database, I'm calling DataTable's Select(string.Empty, string.Empty, DataViewRowState.ModifiedCurrent) and passing this DataRow[] into SqlDataAdapter's Update() method. Unfortunately, Select() doesn't seem to see modified values as modified values because it's returning a DataRow [] with zero elements. This leads me to believe that when a control updates the DataTable, it calls the DataTable's AcceptChanges() method. How do I prevent this from happening? Thanks, Paul Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64106
  - 20
    - Using dataview/datatable to obtain range of rows I want to use a dataview as the source of a datagrid. I have a datatable that has 1000+ rows and I want to provide paging to the client. The ASP.NET paging has a large overhead with _viewstate. I have implemented the following: DataView dv; dv = dtable.DefaultView; DataTable dtemp = dtable.Clone(); for (i=iStartRec; i < iTargetRec; i++) { dtemp.ImportRow(dv[i].Row); } dgCompany.DataSource = dtemp; Question: Can I use a rowfilter to specify a range of records to be contained in the DataView? e.g. dv.RowFilter[51 to 100] that would give me the records from 51 to 100 from the datatable. Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64095
  - 21
    - datagrid problem I have a sql string that I put through a connection object to fetch my data out of vfp tables using the oledb driver, and then bind it to a datagrid in vs.net 2003. The sql contains a left join between 2 numeric fields, and every time the table on the right side of it has no matching record for the first row of the left side table, it causes an error. This never happens if the right side table has a record though, nor on records other than the first. The error is: "The provider could not determine the Decimal value. For example, the row was just created, the default for the Decimal column was not available, and the consumer had not yet set a new Decimal value." Any idea where I am going wrong? -- John Wilson Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64092
  - 22
    - SQL 2000 nasty or my silly mistake? I am using ADO.NET to create a gazetteer from use by a=20 team of botanists requiring to map species distributions=20 world wide. The intention is to place the common Atlas=20 database under MSDE 2000 on a server which will initially=20 be shared by a group on a LAN. We are using VB.NET 2003=20 and MSDE from SP3 for SQL 2000. The gazetteer is required because 60% of the specimens to=20 be mapped have a location description but no latitude and=20 longitude, so a lot of work involves finding out where the=20 specimen came from before plotting it. The gazetteer=20 contains a GeoName table of 7.1M names downloaded from the=20 public domain GeoNet Name Server and Geographical Name=20 Information System. There is also a concordance table of=20 13M words. For example the Atlas contains 13 names=20 containing 'Cape Town' You can find this out in just 0.7=20 seconds even though there are 8099 names with the=20 word 'Town' and 5045 with the word 'Cape'. The concordance=20 is used to lookup just the Id's of the GEONames which are=20 read into a Memory Stream by an SQLDataReader. The join or=20 intersection of the two sets of Ids takes place on the=20 client. The GeoName information is aquired in 20 row=20 chunks only when needed. The result is that the load=20 placed on the server by the individual users at any time=20 is small; MSDE and ADO.NET seem a fine fit for this=20 problem. Another thing the users need from the concordance is what=20 we term _stem_ searches. The problem is that spellings=20 have changed over the years and sometimes herbarium=20 speciment labels are illegible. So we let users hunt for=20 places like 'cay*'. (This is converted internally to=20 LIKE 'cay%'in the stored procedure.) There are 5870 places=20 with a word starting 'cay' in the world atlas (found in=20 about 0.05 seconds) and 570 starting with 'caz' taking=20 less time than this machine will measure. The first (ie=20 the furthest North and West is)is Čazek=E6tnjar'ga in Norway. Note that single letter stems are disallowed for=20 performance reasons - we don't want to scan 20% of the=20 table for e%. Also, because you have to have a two or more=20 letter stem and that's your lot we avoid all the=20 complexities of the LIKE operator which can lead to the=20 server ignoring indexing and scanning the whole table. Yesterday, before I implemented the horrible hack=20 described later, the search for words beginning with 'caz'=20 took over 30 seconds at which time the problem command was=20 terminated. Experimentation showed that searching for any=20 word starting with a stem ending in z had the same effect.=20 There had been a lot of testing of stem searching but no=20 one had used a stem ending in z.=20 The concordance table is created initially by this SQL: CREATE TABLE [Concordance] ( [Word] [char] (8) COLLATE Latin1_General_CI_AS NOT=20 NULL , [GID] [int] NOT NULL , [X] [int] NOT NULL , [Y] [int] NOT NULL=20 The table is then loaded from file using BULK INSERT.=20 Finally the index is created with CREATE UNIQUE CLUSTERED INDEX IX_Prime ON [Concordance] (WORD,Y DESC, X,GID) WITH FILLFACTOR =3D 100 The table is read only. The 'Words' it contains are=20 between 1 and 8 characters which are either lower case a-z=20 or the # sign. The GID field is the ID of the GeoName and=20 X and Y are longitude and latitude in seconds respectively. The relevant fragment of the SQL used for a stem search is: SELECT GID FROM Concordances{0} WHERE (Y <=3D @Y0) AND (Y >=3D @Y1) -- Always true in World AND (X >=3D @X0) AND(X <=3D @x1) -- searches AND (Word Like @Word + '%') ORDER BY Y DESC, X, GID To fix the problem I changed the collation sequence from=20 the database default, as above, to Latin1_General_CS_AS,=20 then Latin_General_BIN. Also I tried using upper case=20 letters instead of lower case letters in the search words.=20 In all cases the result was just the same. Stem searches=20 for sets of letters ending in z were disastrous; all the=20 rest worked fine. Every time I made a change it cost me an unproductive hour=20 whilst my development machine glowed cherry red with the=20 effort of rebuilding 1.18GB of gazetteer. Having slept on=20 the problem I introduced a very nasty fix! It involved=20 modifying two lines of code - and of course rebuilding the=20 gazetteer :-(=20 Once change replaced the letter z with the @ sign whenever=20 a new concordance record was created prior to bulk insert.=20 The second change was at run time, where the z was=20 replaced by @ in the @Word parameter value. The change is=20 completely invisible to the end user; all she notices is=20 that stem searches ending in z are OK now. This only works=20 because the collating order of the concordance isn't=20 really important to our software, all we want to do is=20 search for words that are either equal to @Word or like=20 @Word +'%'. So, is this a well known problem in which case my=20 apologies for wasting your time but please cite references=20 so I can fix it in the approved way. Or is it what a=20 previous boss used to refer to as a 'lacunae' - better=20 known to a less literate generation as a bug?=20 Thanks for your help. Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64089
  - 23
    - How can i see the Sql statement in the sqlcommand ? My code Dim sqlcommand As SqlClient.SqlCommand = New SqlClient.SqlCommand sqlcommand.CommandText = "insert into Supplier( ADDR1 ) values ( @ADDR1 )" sqlcommand.Parameters.Add("@ADDR1", supplierobj.getADDR1) how can i see the sql statement execute in runtime for testing ? Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64088
  - 24
    - sqldatareader and updates I'm a bit confused as to how the sqldatareader oughta be used... so far, I've just assumed that it was only used with SELECT statements and "Provides a means of reading a forward-only stream of rows from a SQL Server database." (from msdn) however, sqldatareader has a RecordsAffected property and the documentation says this property is "The number of rows changed, inserted, or deleted; 0 if no rows were affected or the statement failed; and -1 for SELECT statements." ...implying that sqldatareader can be used to update/insert/delete. If this is so and given sqldatareader's good performance, does this mean that updating with a sqldatareader is faster than updating using the command object's ExecuteNonQuery()? Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64086
  - 25
    - How to post master record? How to post master record? Have two table 'M' and 'D', add relation 'MD', DataGrid1.DataSource = M.DefaultView DataGrid2.DataSource = M.DefaultView DataGrid2.DataMember = "MD" insert record into M, now can insert record into D only after scroll M, how do can without scroll M? thanks, yujin 2003.8.28 Tag: Retrieving available OLEDB Providers and settings programmatically Tag: 64082

Hi there,

(slightly off topic)
is it possible to retrieve the installed OLEDB providers and the
settings they require in a connection string programmatically, by
means of the OLEDB API?
I want to provide something similar to the DataLinks-dialog to
end-users, but in a web browser, configuring data links for a web
server.

Your feedback is much appreciated,
thank you.

Philipp

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