Hello :) I've searched Stackoverflow and Google for a lot of hours and would like to have a clear answer to my problem, because I got a little bit confused. I want to link a table from my PostgreSQL database to my MS Access frontend using VBA. Therefore I'm using the ADO library and installed the 32 bit ODBC driver for PostgreSQL. It works great if I use a connection string with a defined DSN, code looks like this:
Set conn = New ADODB.Connection
Dim strConnect As String
strConnect = "DSN=PostgreSQL35W;Database=...;UID=...;PWD=..."
conn.Open
But the thing is that I dont wan't to use a connection string with DSN, because I dont want to mess around with these DSNs, esspecially not in a distributed environment. Therefore I would like to use a DSN-less connection string. But it seems like that the ADO library doesn't support DSN-less connection strings while using the ODBC driver for PostgreSQL. Is that true?
Here's the code I used for the DSN-less connection:
Set conn = New ADODB.Connection
Dim strConnect As String
strConnect = "ODBC;Driver={PostgreSQL Unicode};Server=...;Port=5432;Database=...;UID=...;PWD=..;TABLE=...
I know there are a lot of threads about that topic, but I couldn't get a clear answer for it. So thank you very much in advance!
Related
I am trying to connect Excel to my Oracle database using VBA.
Sub dbConnect()
Dim cn As ADODB.Connection
Dim rs As ADODB.Recordset
Set con = New ADODB.Connection
Set rs = New ADODB.Recordset
strCon = "Driver={Microsoft ODBC for Oracle}; " & _
"CONNECTSTRING=(description=(address=(protocol=tcp)(host=mydb.domain.com)(port=1522))(connect_data=(sid=mydb))); uid=user; pwd=pw;"
con.Open (strCon)
End Sub
I get an error.
[Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified
I know from other questions and sources that the problem is most likely using the wrong version of the DSN.
However, I don't understand what I need to do to fix it.
My Windows is 64-bit, when I open the ODBC Data Source Administrator I see the following (among others):
Name: Excel Files, Platform: 64-bit, Driver: Microsoft Excel Driver
User DSN
Name: mydb, Platform: 32-bit, Driver: oracle in ORA121020_x86
under System DSN
What can I do to fix it? How do the connection string and the DNSs relate to each other? Should I change the version of one of the DNS and if yes how do I do that?
Edit:
The connection string is copied from the db connection in Oracel SQL Developer where I can access the db.
Ok I managed to fix it. My excel is 64 bit so in order to connect to the db, I had to create a System DNS for my connection that is also 64 bit. In order to do that, I had to go to the /Windows/system32 folder, choose the file odbcad32 and under system DNS add a new DNS with a 64 bit driver I had to download. Lets say I named that DNS abc
I then also changed the connection string that you can see in the above code to
strCon = "Data Source=abc;User=user;Password=pw"
According to this the connection string I used in the post above does not need a DNS, so I don't know why it didn't work, however after creating a new DNS as just described I switched to the new connection string that specifies a DNS.
And voila, after only several hours I was able to connect to my db.
Quick sidenote: As mentioned above, I edited the obcad32 file in /Windows/system32. This is the file for 64 bit DNS. There is a file with the exact same name in the folder /Windows/SysWOW64 that manages the 32 bit DNS, so if you have a similar problem as I had, pay attention to which file you edit.
In VB.net , EOF and BOD not working with ADODB recordset, even I added the right reference
DIM rsReqs as New ADODB.recordset
DIM cn as ADODB.connection
after open connection, with SQL Query I tryed to do this
rsReqs.open(StrSQL,cn)
Do until rsreqs.EOF
....
....
Thank's for your help
You can't use that libraries on vb.net, find the libraries based on your database server. Find more about how to connect your database (like mysql or access) with vb.net by googling.
I'm fairly new to working with Access/VB (started 2 months ago) so bear with me.
I inherited a database that has an ADODB connection to Oracle that works perfect on the Windows 7 machines that it's been tested on (a total of 5), but gives the following error when tested on Windows 10 machines (total of 2). (All machines are running Access 2010).
Run-time Error '3709': The connection cannot be used to perform this operation. It is either closed or invalid in this context.
Here's the code:
Public Function PTMNConnect() As ADODB.Connection
Dim Cn As ADODB.Connection
Dim Conn As String
Conn = "DRIVER={Microsoft ODBC for Oracle};CONNECTSTRING=(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)" & _
"(HOST=host)(PORT=port))(CONNECT_DATA=(SERVICE_NAME=PROD)));uid=username;pwd=password"
Set Cn = New ADODB.Connection
With Cn
.ConnectionString = Conn
.CursorLocation = adUseServer
.Open '**Errors Out on Open**
End With
Set PTMNConnect = Cn
End Function
I've been racking my brain and searching everywhere for a possible solution to this for the past two days with no luck.
Here's what I've tried/verified so far based on other posts I'd seen:
Verified that the Oracle client was installed
Ensured that the Path variable contained the necessary paths
Verified the references and file paths are the same on all machines
Any insight or references that you may be able to provide would be greatly appreciated!
I was able to come up with a fix for this!
It turns out that Windows 7 and Windows 10 have different versions of the {Microsoft ODBC for Oracle} driver which I believe is what was causing the error. I decided to use the Oracle supplied driver (which remains the same for each PC) rather than the Microsoft supplied driver (which, as I found out, varies).
Replacing the Conn string from above with the following code fixed my issue. (This route requires an existing DSN):
Conn = "DRIVER={Oracle in OraClient11g_home1}; Dbq=DSN_TNSServiceName; uid=username; pwd=password"
I have been searching for a couple hours, and found several questions, but none of them really explained this in a way I can understand.
I'm programming a game similar to Rock Paper Sissors, except with many more selections, and the possiblity of a tie. I had originally hardcoded all of the possible outcomes, then decided to try a database so I can learn and practice sql as well.
Problem is, I can't figure out for the life of me how to connect to my local database, now that I have set it up and filled it through Visual Studio 2010. I can connect to it through Server Explorer just fine, and I can see it in Solution Explorer. I've tried several things, along the lines of:
Private sqlConn As New SqlConnection("Data Source=(local)|DataDirectory|\Outcomes.sdf;database=Outcomes;Integrated Security=true")
Private sqlConn As New SqlConnection("Data Source=.\SQLEXPRESS; Integrated Security=true")
Dim sqlConn As SqlConnection
sqlConn = New SqlConnection("DataSource=..\..\Outcomes.sdf")
I am relatively new to sql, but know enough through tinkering to build a sql statement and get me the result I want. But I've never connected to a database before. I've looked on MSDN and tried several things I saw on there (everything that looked like what I needed, really) but it still hasn't worked.
If I can connect, I already have my statement set, and have tested it through the database itself. Any help would be wonderful, especially if it's explained in a way I can understand it and use it for later.
Also, if it helps and isn't noticed through my tried code, my db name is Outcomes. I don't know if that is needed or will help, but just in case.
Please visit connection strings here...
It also would have been helpful to know what type of DBMS you are using as well. I noticed you have an .sdf database file, not a DBMS (For ex: MySql, SQL or Oracle). Therefore, your connection string is really going to depend on what you want.
Your issue is here by the way...
Private sqlConn As New SqlConnection("Data Source=(local)|DataDirectory|\Outcomes.sdf;database=Outcomes;Integrated Security=true")
*You cant use the SqlConnection you have because its not supported with the use of .sdf files.
Instead you have to use: System.Data.SqlServerCe 'This is for compact edition
If you would like to know more about this please see here.
Kendra,
Here are the logical Steps you will need to follow to access the database programmatically:
Note: I'm assumming you have the proper SQLExpress | SQL Server Database setup whether local or remote the methods below are identical except for the connection string information.
1) Import the Sql AdoNet Namespace so you can use the proper SQL Server Client Objects & Methods;
a) Imports System.Data.SqlClient
2) Establish a Connection to the database with the ADO Connection Object:
' Create your ADO Connection Object:
Private myConn As SqlConnection
myConn = New SqlConnection("Initial Catalog=OutComes;" & _
"Data Source=localhost;Integrated Security=SSPI;")
Note: This connection string uses integrated security from your windows machine. you could also use standard security where you would need to enter your username and password credentials. Its your choice.
3) Setup Your ADO Command Object to Define your data retrieval query:
'Create a Command object.
Private myCmd As SqlCommand
myCmd = myConn.CreateCommand
myCmd.CommandText = "SELECT FirstName, LastName FROM Employees"
'Open the connection.
myConn.Open()
Note: Subsitute CommandText string for your actual query based upon your own database schema.
4) Read, Fetch, Display Data using the SQLDataReader Object:
Private results As String
Private myReader As SqlDataReader
myReader = myCmd.ExecuteReader()
'Traverse the DataSet and Display in GUi for Example:
Do While myReader.Read()
results = results & myReader.GetString(0) & vbTab & _
myReader.GetString(1) & vbLf
Loop
'Display results.
MsgBox(results)
5) Gracefully Close all Objects Used:
' Close the reader and the database connection.
myReader.Close()
myConn.Close()
Note - You'll need to consult microsoft for further connection string formats, since I don't have enough info. But this should clarify the actual big picture steps for you.
Regards,
Scott
Connect to a linked table with code.
I have some linked tables from a SQL-server; they are linked with an ODBC connection. The password is not saved with the connection. When I am double clicking on the table in Access table-view I get a prompt for username and password. After entering the password I can view the data in the table.
My problem is when I try to access the table with code before having opened it in this way. What I try to do is to use ADODB to open a recordset with data from the linked table, like:
Dim rst as new ADODB.Recordset
Dim sql as string
Sql = “SELECT * FROM LinkedTable”
rst.Open sql, CurrentProject.Connection, adOpenForwardOnly, adLockReadOnly
Running this code without having access the table before will generate this error: Error# -2147467259, ODBC: connection to dns-name failed.
So, my question is, are there any way to connect to the database with code that can be run when the database is opened? This would also help the users as they would not have to remember a password to the SQL-server.
It seems that you are mixing 2 technologies that might not work together, ie linked tables through ODBC and ADODB recordsets. Have you tried to open DAO recordsets on your linked tables?
Dim rst as DAO.Recordset
Dim sql as string
Sql = “SELECT * FROM LinkedTable”
set rst = currentDb.openRecordset(sql,<your parameters>)
You could of course use ADODB recordsets through 2 ADODB connections, one to your access file, the other one to your SQL server:
Dim rsSQL as ADODB.recordset, _
rsACCESS as ADODB.recordset, _
connectionSQL as ADODB.connection, _
connectionACCESS as ADODB.connection
set connectionSQL = New ADODB.connection
set connectionACCESS = New ADODB.connection
connectionSQL.properties(...) = enumerate your SQL parameters
connectionACCESS.properties(...) = enumerate your ACCESS parameters (use currentproject.accessConnection if your access tables are local tables only)
set rsSQl = New ADODB.recordset
set rsACCESS = New ADODB.recordset
rsSQL.open "SELECT * FROM ...", connectionSQL, <other parameters>
rsACCESS.open "SELECT * FROM ...", connectionACCESS, <other parameters>
Linking ADO recordsets to forms and comboboxes in Access is possible. But, when creating forms, this technology has to be mainly managed through VBA code (you will have to write 'on open' events such as set me.recorset = ...), while the standard "linked tables" technology can be easily used through the user-friendly 'form-design' interface.
You can use a connection string in your code, it is easy enough, seeing you are already using ADO: http://www.connectionstrings.com/
You will need to find out which version of SQL Server you are linking to.