How to connect to DSN created by SQlite Driver using SQL anywhere APIs from C++ code?
I am using db_string_connect() to connect to sybase adaptive server anywhere. I want to use the same function to connect to the DSN created by SQLite Driver as well but db_string_connect() API is returning sqlcode -103 ["You supplied an invalid user ID or an incorrect password."].
I have this somewhat weird requirement because I want to abstract the connection to different databases at ODBC layer. And the code to connect to sybase is already written and I want to minimize the changes in the code. Hope I am making some sense.
Thanks.
You will not be able to use a function from SQL Anywhere client library to connect directly to some other database. Typically, if you need to be able to connect and manipulate different types of database systems, you have to introduce a database layer that sits between the vendor specific client libraries and your code. This could be something you write yourself or use an existing one.
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We need to connect to on premise Teradata from Azure Databricks .
Is that possible at all ?
If yes please let me know how .
I was looking for this information as well and I recently was able to access our Teradata instance from Databricks. Here is how I was able to do it.
Step 1. Check your cloud connectivity.
%sh nc -vz 'jdbcHostname' 'jdbcPort'
- 'jdbcHostName' is your Teradata server.
- 'jdbcPort' is your Teradata server listening port. By default, Teradata listens to the TCP port 1025
Also check out Databrick’s best practice on connecting to another infrastructure.
Step 2. Install Teradata JDBC driver.
Teradata Downloads page provides JDBC drivers by version and archive type. You can also check the Teradata JDBC Driver Supported Platforms page to make sure you pick the right version of the driver.
Databricks offers multiple ways to install a JDBC library JAR for databases whose drivers are not available in Databricks. Please refer to the Databricks Libraries to learn more and pick the one that is right for you.
Once installed, you should see it listed in the Cluster details page under the Libraries tab.
Terajdbc4.jar dbfs:/workspace/libs/terajdbc4.jar
Step 3. Connect to Teradata from Databricks.
You can define some variables to let us programmatically create these connections. Since my instance required LDAP, I added LOGMECH=LDAP in the URL. Without LOGMECH=LDAP it returns “username or password invalid” error message.
(Replace the text in italic to the values in your environment)
driver = “com.teradata.jdbc.TeraDriver”
url = “jdbc:teradata://Teradata_database_server/Database=Teradata_database_name,LOGMECH=LDAP”
table = “Teradata_schema.Teradata_tablename_or_viewname”
user = “your_username”
password = “your_password”
Now that the connection variables are specified, you can create a DataFrame. You can also explicitly set this to a particular schema if you have one already. Please refer to Spark SQL Guide for more information.
Now, let’s create a DataFrame in Python.
My_remote_table = spark.read.format(“jdbc”)\
.option(“driver”, driver)\
.option(“url”, url)\
.option(“dbtable”, table)\
.option(“user”, user)\
.option(“password”, password)\
.load()
Now that the DataFrame is created, it can be queried. For instance, you can select some particular columns to select and display within Databricks.
display(My_remote_table.select(“EXAMPLE_COLUMN”))
Step 4. Create a temporary view or a permanent table.
My_remote_table.createOrReplaceTempView(“YOUR_TEMP_VIEW_NAME”)
or
My_remote_table.write.format(“parquet”).saveAsTable(“MY_PERMANENT_TABLE_NAME”)
Step 3 and 4 can also be combined if the intention is to simply create a table in Databricks from Teradata. Check out the Databricks documentation SQL Databases Using JDBC for other options.
Here is a link to the write-up I published on this topic.
Accessing Teradata from Databricks for Rapid Experimentation in Data Science and Analytics Projects
If you create a virtual network that can connect to on prem then you can deploy your databricks instance into that vnet. See https://docs.azuredatabricks.net/administration-guide/cloud-configurations/azure/vnet-inject.html.
I assume that there is a spark connector for terradata. I haven't used it myself but I'm sure one exists.
You can't. If you run Azure Databricks, all the data needs to be stored in Azure. But you can call the data using REST API from Teradata and then save data in Azure.
I am using R 32 bit and am having an issue trying to get the odbcDriverConnect function to work when trying to connect to an Access database. I have successfully connect to the database using odbcConnect, but am also trying to learn how to use the odbcDriverConnect function.
My code is
scallopdata<-odbcDriverConnect("Driver={Microsoft Access Driver (*.mdb, *.accdb)};Dbq=S://adv/Scallop Central/2014 RSARR/2014 RSA Database_9_3_2014.mdb;
Uid=admin;Pwd=")
When I run the code, I get an error message of
ODBC Microsoft Access Driver Login Failed. Could not find file S://adv/Scallop Central/2014 RSARR/2014 RSA Database_9_3_2014.mdb.
I click the OK button which takes me to a Login box. I select the Database... button. This brings me to a Select Database box where I can select the same database that is specified in the Dbq section of code. Once I select the correct database and click OK I am connected to the database.
I am hoping to use the odbcDriverConnect function so that I do not have to set up a new odbc DSN for each database I would like to access. This may just be me not fully understanding the function.
If any one can provide so insight, it would be very helpful.
Apparently, using AttachDbFilename and user instance in your connection string is a bad way to connect to a DB. I'm using SQL server express on my local machine and it all seems to work fine. But what's the proper way to connect to SQL server then?
Thanks for your explanation.
Using User Instance means that SQL Server is creating a special copy of that database file for use by your program. If you have two different programs using that same connection string, they get two entirely different copies of the database. This leads to a lot of confusion, as people will test updating data with their program, then connect to a different copy of their database in Management Studio, and complain that their update isn't working. This sends them through a flawed series of wild goose chase steps trying to troubleshoot the wrong problem.
This article goes into more depth about how to use this feature, but heed the very first note: the User Instance feature has been deprecated. In SQL Server 2012, the preferred alternatives are (in this order, IMHO):
Create or attach your database to a real instance of SQL Server. Your connection string will then just need to specify the instance name, the database name, and credentials. There will be no mixup as Management Studio, Visual Studio and your program(s) will all be connecting to a single copy of the database.
Use a container for local development. Here's a great starter video by Anna Hoffman and Anthony Nocentino, and I have some other resources here, here, and here. If you're on an M1 Mac, you won't be able to use a full-blown SQL Server instance, but you can use Azure SQL Edge if you can get by with most SQL Server functionality (the omissions are enumerated here).
Use SqlLocalDb for local development. I believe I pointed you to this article yesterday: "Getting Started with SQL Server 2012 Express LocalDB."
Use SQL Server Compact. I like this option the least because the functionality and syntax is not the same - so it's not necessarily going to provide you with all the functionality you're ultimately going to want to deploy. Compact Edition is also deprecated, so there's that.
Of course if you are using a version < SQL Server 2012, SqlLocalDb is not an option - so you should be creating a real database and using that consistently. I only mention the Compact option for completeness - I think that can be almost as bad an idea as using AttachDbFileName.
EDIT: I've blogged about this here:
Bad Habits : Using AttachDBFileName
In case someone had the problem.
When attaching the database with a connection string containing AttachDBFile
with SQLEXPRESS, I noticed this connection was exclusive to the ASP.NET application that was using the database. The connection did block the access to all other processes on the file level when made with System.Data.SqlClient as provider.
In order to assure the connection to be shareable with other processes
instead use DataBase to specify the database name in your connection string
Example or connection string :
Data Source=.\SQLEXPRESS;DataBase=PlaCliGen;User ID=XXX;password=ZZZ; Connect Timeout=30
,where PlaCliGen is the name (or logical name) by which SQLEXPRESS server knows the database.
By connecting to the data base with AttachDBFile giving the path to the .mdf file
(namely : replacing DataBase = PlacliGen by AttachDBFile = c:\vs\placligen\app_data\placligen.mdf) the File was connected exclusively and no other process could connect to the database.
Is there a way to define the calling 'program name' when using the Iseries ODBC driver? When I run a command against our AS400 using the Iseries Access ODBC driver, the calling program in the call stack of the as400 shows the program name as blank. I'd like to define one because we have a trigger that needs to know who is the caller.
The ODBC connection is proxied through a QZDASOINIT job. I don't believe there is a way to identify the specific connection (or program) that fired the trigger.
As JamesA points out, all ODBC requests go through the QZDASOINIT job, so you can't change the call stack to determine the caller.
To get around this problem, DB2 for i includes client special registers that are automatically set by the ODBC driver (which you can override if you wish) and your trigger can then use. For more information see: http://ibmsystemsmag.blogs.com/i_can/2009/10/i-can-use-client-special-registers.html
It's been possible for some time, exposed only since i 6.1. For an example usage, run this statement in i Nav 'Run SQL Scripts...':
select CURRENT CLIENT_APPLNAME, CURRENT CLIENT_PROGRAMID, CURRENT CLIENT_WRKSTNNAME from sysibm.sysdummy1
Support is available to application developers using a JDBC, OLE DB, CLI, or .NET data provider. They can also be set by calling a special stored procedure.
Using IBMDASQL for example, a connection string might include:
conn.Open "Provider=IBMDASQL; Data Source=MyAS400;" & _
"Client User ID=MYWINUSRID; Client WorkStation Name=MYWINPC; " & _
"Client Program ID=somepc.exe; Application Name=Sample for Audit"
The SQL Reference discusses new "special registers".
I have an ASP.NET app that uses a SQL Server database. I now need to pull data from Sybase ASE into that SQL Server database for my app to consume, and I'm not having any success with my ideas.
Has anyone done this? Any ideas/suggestions/tips?
You can configure a linked server from SQL Server to Sybase. It should be fairly vanilla using the Sybase provider on the MS side.
Okay, I've finally (through lame trial and error) found out how to link my Sybase ASE (12.5) server to my SQL Server (2008) which will allow the integration I want. Here's roughly how I did it:
Logged in to Sybase ASE OLE DB Configuration Manager (this is like the Sybase version of Windows' ODBC Data Sources) and added an OLE DB data source. I believe you must be an admin on the PC to do this.
In SQL Server 2008 Management Studio, went to Server Objects > Linked Servers. Right click and select "New Linked Server".
In the Linked Server Properties, I set the following properties:
General:
--Linked server: the name of your linked server as you want it to appear in your linked server list
--Provider: Select Sybase ASE OLE DB Provider from the dropdown list.
--Product name: The exact name of the OLD DB data source you just created in Sybase ASE OLE DB Configuration Manager.
--Data source: Same as Product name.
--Provider string: I left this blank
--Location: I left this blank
--Catalog: The default database (master or whatever) to log on to.
Security:
--You need to map a valid SQL Server logon to a valid Sybase logon. I did not use impersonation (which does a credentials pass-thru).
--I chose my connection Be made without using a security context.
Server Options:
--All the defaults worked for me.
Throughout, the standard SQL Server help worked fairly well as a guide. Though not always true, F1 was my friend here.
I can now do distributed queries, DTS or SSIS packages, and use SSRS. This takes a lot of the suck out of Sybase ASE.
Of course the above can be done via the command line using sp_linkserver, but the GUI is more comfortable for a lowly dev like me.
Use Management Studio or Enterprise Manager to import the data using the data importation wizard. That should be it, just make sure you pick the right data provider in the wizard and you should be good to go.
If you want this to be a live feed create a small windows service to manage the exchange of information. It should be relatively simple to do, just a little bit of leg work on your end. If you are adverse to that there are plenty of off the shelf solutions that can do this for you.
The question is a little vague on specifics:
Is this a one time conversion or part of a repeated process.
Is the source machine "reachable" from your destination machine (can you connect the two or do you need to read in files)
With most conversions there are two parts:
Physically getting data from the source into the destination.
Mapping data from the source to the destination tables.
It is hard to make any recommendations without more info. What would be fine for a one time conversion would not work if you need to read in data all day every day. Also, if the source database can not be connected to and you have to pass files, they methods change.