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DB2 Connection using C#.Net - Ms Visual Studio

I am trying to connect Db2 through c#.net
DB2Command MyDB2Command = null;
String MyDb2ConnectionString = "database=<alias>;uid=<username>;pwd=<password>;";
DB2Connection MyDb2Connection = new DB2Connection(MyDb2ConnectionString);
MyDb2Connection.Open();
Getting below error on MyDb2Connection.open():
SQL1159 Initialization error with DB2 .NET Data Provider, reason code 10, tokens 0.0.0, 9.7.4,
Kindly help me to resolve the issue.
In application folder I have already put db2app.dll and db2app64.dll
Db2 Version: 9.7.4

How to connect to oracle database with ODAC c#

I am using this code but getting an error of 'Object reference not set to an instance of an object.' at con.open() ? what am I doing wrong ?
I have already download and installed ODAC component version 10 , 11 ,12 trying each one at the failure of the latest one but still same error
using Oracle.DataAccess.Client;
namespace WindowsFormsApplication1
{
class OraTest
{
public OracleConnection con = new OracleConnection();
public void Connect()
{
con.ConnectionString = "Data Source=(DESCRIPTION= (ADDRESS = (PROTOCOL = TCP)(HOST =myip) (PORT = myport))(CONNECT_DATA = (SERVER = dedicated)(SERVICE_NAME = mydb)));User ID=myid;Password=mypass;";
con.Open(); //error here
}
public void Close()
{
con.Close();
con.Dispose();
}
}

Please go through this link
Getting Started with Oracle Data Provider for .NET (C# Version)
http://www.oracle.com/webfolder/technetwork/tutorials/obe/db/dotnet/GettingStartedNETVersion/GettingStartedNETVersion.htm

If you add a try/catch block in Connect(), you'll be able to catch the error.
For example:
When opening an oracle connection, connection object is null
I added the try catch block, and it returned ORA12154 - TNS could not
be resolved. After some research, I added an SID to my tnsnames.ora
file in my ODP for .NET Oracle home path, and it worked
See also Troubleshooting Oracle Net Services for troubleshooting possible connection issues from Oracle clients (such as your C# program).
But your first step is absolutely to determine the Oracle-level error (for example, ORA-12543 (could not connect to server host) or TNS-12514 (could not find service name)
MSDN: OracleException Class
public void ShowOracleException()
{
OracleConnection myConnection =
new OracleConnection("Data Source=Oracle8i;Integrated Security=yes");
try
{
myConnection.Open();
}
catch (OracleException e)
{
string errorMessage = "Code: " + e.Code + "\n" +
"Message: " + e.Message;
System.Diagnostics.EventLog log = new System.Diagnostics.EventLog();
log.Source = "My Application";
log.WriteEntry(errorMessage);
Console.WriteLine("An exception occurred. Please contact your system administrator.");
}
}
It's significant that con.ConnectionString = xyz works, but the following `con.Open()" fails. This means .Net is creating the C# object, but Oracle/TNS is failing when you try to use it.
ADDITIONAL SUGGESTIONS:
Re-read
When opening an oracle connection, connection object is null.
Read all of the suggestions, including the one about "Data Source in your connection string".
Focus on your connection string. It couldn't hurt to specify the connection string in your OracleConnection() constructor, if possible. Here's another link:
ODP.NET Connection exception
It would be great if you can verify connectivity from your PC with some other Oracle client, besides your C#/.Net program. To verify you're talking to the right TNS host and service, with the correct username/password. For example, maybe you have SQLDeveloper or sqlplus.
Finally, re-read the TNS troubleshooting link:
https://docs.oracle.com/cd/E11882_01/network.112/e41945/trouble.htm#NETAG016

What worked for me with the same error was to simply switch from the 'plain' Oracle DataAccess library, to the 'Managed' version.
This is an extemely easy change to make -
Add a Reference in your c# project to the Oracle.ManagedDataAccess library
Replace the existing use statements at the top of your Oracle client code with the following:
using Oracle.ManagedDataAccess.Client;
using Oracle.ManagedDataAccess.Types;
Include the Oracle.ManagedDataAccess.dll file with your exe

SEHException on OleDb connection open

I'm developing a small application that will simplify logging, it does so by adding some inputs to an MS Access database through OleDB.
let private conn = new OleDbConnection(connectionString)
let private submitCmd date wins =
let cmd = new OleDbCommand("INSERT INTO ArenaStats ([Date], [Wins]) VALUES (#Date, #Wins)",
Connection = conn, CommandType = CommandType.Text)
["#Date", box date; "#Wins", box wins]
|> List.iter (cmd.Parameters.AddWithValue >> ignore)
cmd
let private submit date wins =
try
conn.Open()
(submitCmd date wins).ExecuteNonQuery() |> ignore
finally
conn.Close()
[<CompiledName "AddEntry">]
let addEntry(date:DateTime, wins:int) =
submit date wins
Now testing this through FSI works just as expected. However, when I consume this API from a C# WPF project it will throw an SEHException at conn.Open(). I am really scratching my head over why this is happening.
Edit
As suggested, I have also tried to implement the same code purely in C# and in the same project, it will throw the same exception at the same place but I am posting the code below for reference.
class MsAccessDatabase : IArenaWinsDatabase {
private OleDbConnection connection = new OleDbConnection(connectionString);
private OleDbCommand SubmitCommand(DateTime date, int wins) {
return new OleDbCommand("INSERT INTO ArenaStats ([Date], [Wins]) VALUES (#Date, #Wins)") {
Connection = connection,
CommandType = System.Data.CommandType.Text,
Parameters = {
new OleDbParameter("#Date", date),
new OleDbParameter("#Wins", wins)
}
};
}
public void Submit(DateTime date, int wins) {
try {
connection.Open();
SubmitCommand(date, wins).ExecuteNonQuery();
}
finally {
connection.Close();
}
}
}

With some help from Philip I was able to figure it out. It seems that by default FSI is configured to run in 64-bit by default while the WPF project is set to "prefer 32-bit". Changing the target platform for the WPF project to 64-bit resolved the issue.

When trying to run the following code:
var connectionString = string.Format("Provider=Microsoft.ACE.OLEDB.12.0;Data Source={0}; Extended Properties=Excel 12.0;", FilePath);
OleDbConnection OleDbConnection = new System.Data.OleDb.OleDbConnection(connectionString);
OleDbConnection.Open();
An SEHException exception is thrown at runtime, with the error message 'External Component has thrown an Exception'
This will usually occur when the build configuration platform in Visual Studio is incorrect, this can occur in both build configuration platforms, x86 and x64.
This is due to a mismatch between the build configuration platform of your project and the Microsoft Access Database Engine which is installed on your machine.
In order to resolve this error:
Change the build configuration platform in Visual Studio - make sure it matches the Microsoft Access Database Engine version on your machine
Recompile and run your project
The run time error should now be resolved

I know this is a really old thread, but I just ran into the same problem with a different solution.
When I installed the Access Database Engine 2016 Redistributable (x64) for the ACE provider the installer gave me an error that VCRUNTIME140.DLL wasn't installed, but the installer completed anyways and the ACE provider was available.
Uninstalling the Access Database Engine, installing the VC++ 2015 Redistributable R3 (https://www.microsoft.com/en-us/download/confirmation.aspx?id=52685), then re-installing the Access Database Engine solved the problem.

Informix db connection and loading to datatable is not working

i am trying to connect to an informix database in my web application and retrieve the data based on an item code entered by the user and store it in a datatable later i want to take the data from the datatable and display it on my textboxes for the item selected. its an odbc connection DRIVER={IBM INFORMIX ODBC DRIVER} in my connection string
if (DropDownList4.Text == "***.**.**.**" || DropDownList4.Text == "***.**.**.**" || DropDownList4.Text == "***.**.**.**")
{
//string abilene = ConfigurationManager.ConnectionStrings["Abeliene"].ConnectionString.ToString();
IfxConnection conn = new IfxConnection("User Id=****;Password=****;" +"Host=abkrisc1;Server=abkrisc1;" +"Service=1719;DB=circa119;");
DataTable Abilene = new DataTable();
Abilene.Columns.Add("item");
Abilene.Columns.Add("desc");
Abilene.Columns.Add("upc");
Abilene.Columns.Add("itemupc");
Abilene.Columns.Add("ctyp");
Abilene.Columns.Add("citg");
Abilene.Columns.Add("best");
Abilene.Columns.Add("disp");
Abilene.Columns.Add("mold");
Abilene.Columns.Add("csel");
IfxCommand cmd;
cmd = new IfxCommand("Select t_item,t_idsc,t_upct,t_item_upc,t_ctyp,t_citg,t_best,t_disp,t_mold,t_csel from tsckcm907 where t_item = #item'");
conn.Open();
cmd.Parameters.Add("#item", IfxType.VarChar).Value = TxtItem.Text;
try
{
IfxDataReader myreader = cmd.ExecuteReader();
Abilene.Load(myreader);
Response.Write(Abilene.Columns);
con = true;
}
catch (Exception ex)
{
throw ex;
con = false;
}
if (con == true)
{
while (Abilene.Rows.Count > 0)
{
TxtItem.Text = Abilene.Rows[0]["item"].ToString();
lbldesc.Text = Abilene.Rows[1]["desc"].ToString();
}
}
The error i get when i debugged was at conn.open() -> ERROR [HY000] [Informix .NET provider][Informix]Server abkrisc1 is not listed as a dbserver name in sqlhosts.
i have done a similar scenario with sql database, but informix i have never worked with. Please if anyone could help me with this code that would be awesome, even this code that i used was found from ibm website.

Check your informix server configuration (the problem might be in your sqlhosts file, as the error states), it should contain server with the name abkrisc1, listening at port 1719.
If that's ok, then check your DSN configuration (this may vary depending on your operating system - check out this page for details).

Documentation in internet and the error message are misleading.
I had the same error and meanwhile I found out how to solve it.
When you install the Informix Client SDK for Windows and use the ODBC driver for Informix (with or without .NET) you must pass the following parameters:
Host
Server
Service or Port
Protocol
User ID
Password
All these parameters are mandatory. The database is optional.
In your connection string the protocol is missing. In the case that any parameter is missing the OBDC driver searches the server in the registry under
32 bit driver:
HKLM\Software\Wow6432Node\Informix\SQLHOSTS\Servername
64 bit driver:
HKLM\Software\Informix\SQLHOSTS\Servername
If the server is not listed there you get the error "Server XYZ is not listed as a dbserver name in sqlhosts."
Please note that only Linux uses an sqlhosts file. On Windows the same data is stored in the registry instead.
You do NOT need to create a sqlhosts file although the error message and the documentation and several webpages make you think that.
You do NOT need to use the IBM tool SetNet32 to generate entries for your server.
You just have to pass ALL mandatory parameters to the ODBC driver and the error is gone.
It is really a pitty that IBM is not able to give a more intelligent error message.

OracleDataAdapter.Fill "Connection must be open" error

I have some code that uses ODP.Net
using (OracleConnection connection = new OracleConnection(connectionString))
{
connection.Open();
boxCommand = new OracleCommand(sql, connection);
OracleDataAdapter boxAdapter = new OracleDataAdapter(boxCommand);
DataTable boxTable = new DataTable();
boxAdapter.Fill(boxTable);
}
I then get an error below on a production server. The test server is fine.
I don't understand as its complaining about a connection not being open but if there was a problem it should occur at the point my Open is called not on the Fill. Also I thought Fill was supposed to open the connection anyway.
Can anyone suggest what might be going on?
UPDATE: From the comments I tried adding this but same problem:
using (OracleConnection connection = new OracleConnection(connectionString))
{
connection.Open();
while(connection.State != ConnectionState.Open)
{
connection.Close();
connection.Open();
}
boxCommand = new OracleCommand(sql, connection);
OracleDataAdapter boxAdapter = new OracleDataAdapter(boxCommand);
DataTable boxTable = new DataTable();
boxAdapter.Fill(boxTable);
}
UPDATE 2 : I have added logging and the Validate Connection = true to the connection string and I know the connection state is open, the box command was done, the adapter created and the table created, it definitely errors on the Fill

Can you try installing the latest version of ODP.Net and see if you still have the problem? You should be able to run latest ODP.Net even against older Oracle DBs (10g in your case).
EDIT:
Since you're restricted to a specific ODP.net version, here are some other things to try:
Make sure the proper Oracle folders are at the beginning of your system path. For example, I have the Oracle folders at the beginning of my path, like this (I have ODP.net installed in c:\oracle\ora11g and I also have Oracle 10g Express Edition installed, but note that the ODP.net folders are first:
c:\oracle\ora11g\product\11.1.0\client_1;c:\oracle\ora11g\product\11.1.0\client_1\bin;C:\oracle\ora10g\bin;
I've seen situations where Oracle does weird things and won't work properly if the path isn't correct.
Try reinstalling the specific ODP.net version you are using. This should clean things up and hopefully resolve your issue.