Fundamental help required with SQL connection

I am writing SQL data apps using VB.NET 2003, MSDE is being used as the
server.

When I create and instance of the server, it has a the format
machinename/instancename

This is fine for the developement machine but how does my code connect to
the server when it is on another machine ? When an instance of MSDE is run
on the target, it will produce...
anotherPCname/instancename

Thanks for any helpThe 'Data Source' keyword in the connection string specifies the SQL Server
instance you want to connect to. A best practice is to store the connection
string externally (e.g. config file) rather than hard-code it in your app so
that you can connect to different servers without changing code. Connection
string examples:

Local default instance:
Data Source=ThisServer;Initial Catalog=MyDatabase;Integrated Security=SSPI

Local named instance:
Data Source=ThisServer\ThisInstance;Initial Catalog=MyDatabase;Integrated
Security=SSPI

Remote default instance:
Data Source=OtherServer;Initial Catalog=MyDatabase;Integrated Security=SSPI

Remote named instance:
Data Source=OtherServer\OtherInstance;Initial Catalog=MyDatabase;Integrated
Security=SSPI

--
Hope this helps.

Dan Guzman
SQL Server MVP

"David" <david@.orbitcoms.com> wrote in message
news:YNvEc.71214$sj4.25491@.news-server.bigpond.net.au...
> I am writing SQL data apps using VB.NET 2003, MSDE is being used as the
> server.
> When I create and instance of the server, it has a the format
> machinename/instancename
> This is fine for the developement machine but how does my code connect to
> the server when it is on another machine ? When an instance of MSDE is run
> on the target, it will produce...
> anotherPCname/instancename
> Thanks for any help
>|||Dan,

Thanks for the reply.

So, I just need to create a text file with the connection string with say

the local machine ID and database name. The application loads this at boot

and

connects to the named server.

When I deploy the application, I have the client alter the text file by

finding

the machine name and modifying the text to suit ??

I suppose I could use a Try Catch and have try with the local settings and

if it fails

it loads the file in the catch sub (or maybe the string is stored in

registry).

One thing I am also unable to find out is. How does MSDE know where the file

is located on the third party machine ? Should the Initial Catalog =

Path+dasename ?

Thanks

"Dan Guzman" <danguzman@.nospam-earthlink.net> wrote in message
news:FayEc.70$oD3.17@.newsread1.news.pas.earthlink. net...
> The 'Data Source' keyword in the connection string specifies the SQL
Server
> instance you want to connect to. A best practice is to store the
connection
> string externally (e.g. config file) rather than hard-code it in your app
so
> that you can connect to different servers without changing code.
Connection
> string examples:
> Local default instance:
> Data Source=ThisServer;Initial Catalog=MyDatabase;Integrated Security=SSPI
> Local named instance:
> Data Source=ThisServer\ThisInstance;Initial Catalog=MyDatabase;Integrated
> Security=SSPI
> Remote default instance:
> Data Source=OtherServer;Initial Catalog=MyDatabase;Integrated
Security=SSPI
> Remote named instance:
> Data Source=OtherServer\OtherInstance;Initial
Catalog=MyDatabase;Integrated
> Security=SSPI
> --
> Hope this helps.
> Dan Guzman
> SQL Server MVP
> "David" <david@.orbitcoms.com> wrote in message
> news:YNvEc.71214$sj4.25491@.news-server.bigpond.net.au...
> > I am writing SQL data apps using VB.NET 2003, MSDE is being used as the
> > server.
> > When I create and instance of the server, it has a the format
> > machinename/instancename
> > This is fine for the developement machine but how does my code connect
to
> > the server when it is on another machine ? When an instance of MSDE is
run
> > on the target, it will produce...
> > anotherPCname/instancename
> > Thanks for any help|||Hi

To connect to a different instance/server that is running your database then
the connection string will need to be changed. Quite often this sort of
thing is held in the registry and you configure it on installation.
Alternatively you may want to provide a small application to configure the
settings.

http://www.microsoft.com/sql/msde/t...integration.asp

John

"David" <david@.orbitcoms.com> wrote in message
news:YNvEc.71214$sj4.25491@.news-server.bigpond.net.au...
> I am writing SQL data apps using VB.NET 2003, MSDE is being used as the
> server.
> When I create and instance of the server, it has a the format
> machinename/instancename
> This is fine for the developement machine but how does my code connect to
> the server when it is on another machine ? When an instance of MSDE is run
> on the target, it will produce...
> anotherPCname/instancename
> Thanks for any help
>|||Thanks again for the replies.

I have tried a hard-coded option of connection and it worked.

ie.

TRY
sqlconnectionstring = ...... originalmachinename......password=..."
CATCH
sqlconnectionstring = ...... newmachinename......password=..."
END TRY

I tried to hook this into a config file but I had trouble(I used the wizard
in VB.NET to make the connection string and edited it but the area the code
was placed did not seem to like me playing with the code adding file open
command etc.

I will try by completely coding the connection in the main form load
routine.
Like this

TRY
Load my original instance for development and test
CATCH
read registry and see if validconnect string exists
if so then try to connect else
prompt user for PC name
save name to registry
try to connect
FINALLY
give up
END TRY

would this approach seem reasonable ?

"John Bell" <jbellnewsposts@.hotmail.com> wrote in message
news:_FyEc.6675$%N6.73110644@.news-text.cableinet.net...
> Hi
> To connect to a different instance/server that is running your database
then
> the connection string will need to be changed. Quite often this sort of
> thing is held in the registry and you configure it on installation.
> Alternatively you may want to provide a small application to configure the
> settings.
> http://www.microsoft.com/sql/msde/t...integration.asp
> John
> "David" <david@.orbitcoms.com> wrote in message
> news:YNvEc.71214$sj4.25491@.news-server.bigpond.net.au...
> > I am writing SQL data apps using VB.NET 2003, MSDE is being used as the
> > server.
> > When I create and instance of the server, it has a the format
> > machinename/instancename
> > This is fine for the developement machine but how does my code connect
to
> > the server when it is on another machine ? When an instance of MSDE is
run
> > on the target, it will produce...
> > anotherPCname/instancename
> > Thanks for any help|||Hi

This may help:
http://support.microsoft.com/defaul...kb;en-us;309485
http://support.microsoft.com/defaul...kb;EN-US;283245

John

"David" <david@.orbitcoms.com> wrote in message
news:qazEc.71562$sj4.10264@.news-server.bigpond.net.au...
> Thanks again for the replies.
> I have tried a hard-coded option of connection and it worked.
> ie.
> TRY
> sqlconnectionstring = ......
originalmachinename......password=..."
> CATCH
> sqlconnectionstring = ...... newmachinename......password=..."
> END TRY
> I tried to hook this into a config file but I had trouble(I used the
wizard
> in VB.NET to make the connection string and edited it but the area the
code
> was placed did not seem to like me playing with the code adding file open
> command etc.
> I will try by completely coding the connection in the main form load
> routine.
> Like this
> TRY
> Load my original instance for development and test
> CATCH
> read registry and see if validconnect string exists
> if so then try to connect else
> prompt user for PC name
> save name to registry
> try to connect
> FINALLY
> give up
> END TRY
> would this approach seem reasonable ?
> "John Bell" <jbellnewsposts@.hotmail.com> wrote in message
> news:_FyEc.6675$%N6.73110644@.news-text.cableinet.net...
> > Hi
> > To connect to a different instance/server that is running your database
> then
> > the connection string will need to be changed. Quite often this sort of
> > thing is held in the registry and you configure it on installation.
> > Alternatively you may want to provide a small application to configure
the
> > settings.
> > http://www.microsoft.com/sql/msde/t...integration.asp
> > John
> > "David" <david@.orbitcoms.com> wrote in message
> > news:YNvEc.71214$sj4.25491@.news-server.bigpond.net.au...
> > > I am writing SQL data apps using VB.NET 2003, MSDE is being used as
the
> > > server.
> > > > When I create and instance of the server, it has a the format
> > > machinename/instancename
> > > > This is fine for the developement machine but how does my code connect
> to
> > > the server when it is on another machine ? When an instance of MSDE is
> run
> > > on the target, it will produce...
> > > anotherPCname/instancename
> > > > Thanks for any help
> > > >|||I finally have the problem figured out. I needed to ATTACH the database to
sql server (MSDE2000) using the osql utility.

Now, would someone be able to explain how I can automate the attachment at
the customer end.
Preferably, I would like my VN.NET application install to copy the
unattached database files and attach them to the MSDE server.

Thanks

"David" <david@.orbitcoms.com> wrote in message
news:YNvEc.71214$sj4.25491@.news-server.bigpond.net.au...
> I am writing SQL data apps using VB.NET 2003, MSDE is being used as the
> server.
> When I create and instance of the server, it has a the format
> machinename/instancename
> This is fine for the developement machine but how does my code connect to
> the server when it is on another machine ? When an instance of MSDE is run
> on the target, it will produce...
> anotherPCname/instancename
> Thanks for any help
>|||Hi
I am totally new to the VB.net, only learn this about two weeks. I
used codes from MS to create a file upload class then add function to
store the uploaded filename to a table in SQL server. However I kept
getting the error message about "cannot connect to database" No matter
what format I used. I have tried at least two dozen connection stringe
formats either in Sqlconnection or OleDBConnection. Here is the basic
formats that I used:
strCon = "Data Source =localhost;Password=;User ID=sa;Initial
Catalog=Northwind" for SqlConnection
strCon = "Provider=SQLOLEDB.1;User ID=sa;Password=;Persist Security
Info=True;Initial Catalog=Northwind;Data Source=FAL-L6388" for
OleDbConnection.
I use SQL 7, which was installed by default, i,e only have user ID =
sa, no password, use the default Northwind database. That's all. My
Server is local named FAL-L688.
I have replaced the Data Source with Server= but still give me same
error. I even used an udl to create the OleDB coonnection and put
into my string, still NO. I have exhauseted all alternatives. Does
anyone have clue? Is anyway to debug the trasaction? so i can find out
what went wrong?|||Here is my codes:
Imports System.Data.OleDb
Imports System.Configuration
...
Dim oCon As New OleDbConnection
Dim oCmd As New OleDbCommand
oCon = New OleDbConnection(ConfigurationSettings.AppSettings( "strCon"))
oCon.Open()

oCmd.CommandType = CommandType.StoredProcedure
oCmd.CommandText = "set_order_attachments"
oCmd.Parameters.Add("@.cart_id", OleDbType.VarChar, 15, cart_id)
oCmd.Parameters.Add("@.attachment", OleDbType.VarChar, 255,
strFilenamesCollection)
oCmd.Connection = oCon
Try
oCon.Open()
oCmd.ExecuteNonQuery()
...
And I have fololowing setting in the Web.config file under the
<configuration>
<appSettings>
<add key="strCon"
value="Provider=SQLOLEDB.1;User ID=sa;Password=;Initial
Catalog=Northwind;Server=(local);" />
</appSettings>
Also tried to use "Data Source=.." and enter my local machine name
there.
None of them work , came back the same "Non DB connection"

C Chang|||There was a duplicated "oCon.Open()" in my codes, but removal it does
not help. However, I tried to use the OracleCommand with the SQL query
script directly and IT WORKS!. Does anyone know why it does not work
with the Oracle procedure. I hate to change all my procedure calls to
in-line scripts. Besides if there is a complicated procedure then the
query becomes a problem.|||(chi-soon_x_chang@.raytheon.com) writes:
> There was a duplicated "oCon.Open()" in my codes, but removal it does
> not help. However, I tried to use the OracleCommand with the SQL query
> script directly and IT WORKS!. Does anyone know why it does not work
> with the Oracle procedure. I hate to change all my procedure calls to
> in-line scripts. Besides if there is a complicated procedure then the
> query becomes a problem.

I'm getting confused, are you connecting to SQL Server or to Oracle?

To go back to your original code, the error message seems like it
would from your own code. That is, I cannot really recall any error
that says "Cannot connect to database". It would help, if you could
get hold of the actual message from the client library. To that end,
it would help if you posted more parts of the code, and also if you
found out on exactly which statement, things go wrong.

Stupid check: you have SQL Server running, haven't you?

--
Erland Sommarskog, SQL Server MVP, esquel@.sommarskog.se

Books Online for SQL Server SP3 at
http://www.microsoft.com/sql/techin.../2000/books.asp|||Hi

In addition to Erlands comments, you may want to move the try block earlier
to catch the connection error. Also check out
http://www.connectionstrings.com/ for the connection string, I think you
should be using Data Source instead of Server. Try using the IP address
instead of the name if necessary.

John

<chi-soon_x_chang@.raytheon.com> wrote in message
news:1103838243.185277.162240@.z14g2000cwz.googlegr oups.com...
> There was a duplicated "oCon.Open()" in my codes, but removal it does
> not help. However, I tried to use the OracleCommand with the SQL query
> script directly and IT WORKS!. Does anyone know why it does not work
> with the Oracle procedure. I hate to change all my procedure calls to
> in-line scripts. Besides if there is a complicated procedure then the
> query becomes a problem.