Accessing an Oracle database with vb.net

[Mark Brown]

I'm trying to access an Oracle database vb.net. I found several examples.
I tried following each one, but I get the same error no matter what I try.
I don't really understand what the error means (I've never tried accessing
an Oracle database before). The error I get is:

ORA-12514: TNS:listener does not currently know of service requested in
connect descriptor

I installed the oracle dll and added it as reference (I get the same error
if I use the Oracle reference that came with VS2003.) I figure it's hitting
the database ok since if I change the name of the database it's connecting
to, I get an error that it couldn't resove the name. Here's the code I'm
using, pretty much straight from the example on Oracle's web site:

Dim con As OracleConnection = New OracleConnection

con.ConnectionString = "User ID=scott;Password=tiger;Data Source=oracledb;"

Try

con.Open()

Catch ex As Exception

tmp = ex.Message

End Try

Naturally, I'm using different user id, password and db name in my actual
code. The program errors on the con.Open() line.

Any ideas on where to look would be greatly appreciated.

Mark

[Patrick Steele]

In article <e#**************@TK2MSFTNGP03.phx.gbl>, mb****@echd.no-
spam.org says...

I'm trying to access an Oracle database vb.net. I found several examples.
I tried following each one, but I get the same error no matter what I try.
I don't really understand what the error means (I've never tried accessing
an Oracle database before). The error I get is:

ORA-12514: TNS:listener does not currently know of service requested in
connect descriptor

I installed the oracle dll and added it as reference (I get the same error
if I use the Oracle reference that came with VS2003.) I figure it's hitting
the database ok since if I change the name of the database it's connecting
to, I get an error that it couldn't resove the name.

It's been a few years since I had to deal with Oracle, but I'll give it
a shot.

First, when you say you "installed the oracle dll", does that mean you
actually installed the oracle client? If not, I would install the
oracle client and include SQL plus during the installation. SQL Plus is
a kind of isql/w (if you're familiar with SQL Server).

Once the client is installed, make sure you tnsnames.ora file is
configured correctly. This, I can't help you with since I don't
remember what is necessary, but I do recall that was a source for
frequent frustration.

Third, make sure the Oracle listener service is running on the oracle
server.

Good luck!

--
Patrick Steele
http://weblogs.asp.net/psteele

[Mark Brown]

"Patrick Steele" <pa*****@mvps.orgwrote in message
news:MP************************@msnews.microsoft.c om...

In article <e#**************@TK2MSFTNGP03.phx.gbl>, mb****@echd.no-
spam.org says...

>I'm trying to access an Oracle database vb.net. I found several
examples.
I tried following each one, but I get the same error no matter what I
try.
I don't really understand what the error means (I've never tried
accessing
an Oracle database before). The error I get is:

ORA-12514: TNS:listener does not currently know of service requested in
connect descriptor

I installed the oracle dll and added it as reference (I get the same
error
if I use the Oracle reference that came with VS2003.) I figure it's
hitting
the database ok since if I change the name of the database it's
connecting
to, I get an error that it couldn't resove the name.

It's been a few years since I had to deal with Oracle, but I'll give it
a shot.

First, when you say you "installed the oracle dll", does that mean you
actually installed the oracle client? If not, I would install the
oracle client and include SQL plus during the installation. SQL Plus is
a kind of isql/w (if you're familiar with SQL Server).

Once the client is installed, make sure you tnsnames.ora file is
configured correctly. This, I can't help you with since I don't
remember what is necessary, but I do recall that was a source for
frequent frustration.

Third, make sure the Oracle listener service is running on the oracle
server.

Good luck!

Thanks for the reply. I do have the client installed and I can access the
database using Query Builder. But in my application, when it tries to
connect, I get that error, which from what I've been able to find out means
that I contacted the server, but not registered with the listener. But no
one ever seems to mention how to do that.

Mark