U-SQL data source as SQL Server inside a UDF - c#

I need to extract rows from a SQL table where some columns are encrypted using SQL Server's new 'Always Encrypted' feature. I see that I cannot use the 'AZURESQLDB' DataSource feature and there needs to be decryption done before reading the data in plain text. Are there plans to add this capability?. Meanwhile, I tried to write a user defined function that will do the same operation(connect, decrypt data and return object) in a registered assembly but when it runs, I get the following error:
Inner exception from user expression: A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server)
I have checked the code and everything seems correct. The connection string is used by the SqlConnection object and works fine in all other applications. I am guessing that the connectivity to external data sources from within a UDF is blocked. Is there any way around this?

Are you using the DATA SOURCE in U-SQL for representing your SQL Server instance and you cannot get it to read encrypted data? If so, please file a feature request at http://aka.ms/adlfeedback.
You cannot call out to network resources directly from within U-SQL user code for the reasons explained here.

One way around this might be to create a stored procedure which does the hard work, the decryption then renders the data. Then use Azure Data Factory with a Stored Proc Task to access the decrypted data and move what you need to the Data Lake - not including the secure data. From there you could then access it using a U-SQL script. One idea? Let me know if you need me to work up more of an example.

Related

UWP the application cannot communicate with the remote instance SQL Server

I am currently implementing a UWP program for an existing database. I took this article as a basis.
https://learn.microsoft.com/en-us/windows/uwp/data-access/sql-server-databases
When running, I get an exception:
System.Data.SqlClient.SqlException" в System.Data.SqlClient.dll
Exception:
A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: TCP Provider, error: 25 - Connection string is not valid)
This seemed strange to me, since a WPF application with the same connection string works fine. Next, I decided to install a database instance on my computer and export some of the data to a local database. To my surprise, after replacing the connection string from:
Data Source=sqlserver\sqlexpress
to
Data Source=.\sqlexpress
UWP program read this from the database on my computer.
I also read this article to make sure that the remote database is configured correctly. https://www.lansweeper.com/knowledgebase/a-network-related-or-instance-specific-error-occurred/
As I said, WPF programs work with this database perfectly. What are the ways to check why the UWP doesn't want to communicate with the database?
to make it clear whether the remote server is available in principle, I apply the output of the TNC command:
tnc sqlserver -p 1433 -I detailed
ComputerName : sqlserver
RemoteAddress : 192.168.10.11
RemotePort : 1433
NameResolutionResults : 192.168.10.11
MatchingIPsecRules :
NetworkIsolationContext : Private Network
InterfaceAlias : Ethernet
SourceAddress : 192.168.10.20
NetRoute (NextHop) : 0.0.0.0
TcpTestSucceeded : True
Connection string look like:
private string connectionString = #"Data Source=sqlserver\sqlexpress;Initial Catalog=TestCatalog;User ID=*;Password=*";
The same connection string is used in VS. VS shows the contents of the table without problems. I can also delete or add new lines in the VS editor.
I'm talking about a remote database. In VS server Explorer I have a Data Connection where I am connected to a remote database. I can safely edit remote database data in VS (add, delete and update). I see the connection string and originally used it as the connection string in UWP app.
You have already taken a look at this microsoft link here. Long story short, have you followed the proposal below?
Trouble connecting to your database?
In most cases, some aspect of the SQL Server configuration needs to be changed. If you're able to connect to your database from another type of desktop application such as a Windows Forms or WPF application, ensure that you've enabled TCP/IP for SQL Server. You can do that in the Computer Management console.
Check to see if you have followed the rest of the solution properly. You might need to enable the tcp port from the window firewall.
Go to firewall -> Inbound Rules -> Add TCP:1433 in the rule.
Also since the error is about the connection string, try to use only the server name/ ip/ or hostname, without the server instance.
You can also add the port number and see if this works for you. When you add it, sql server ignores the instance name (as different instances require different ports to work, so it can work as a unique identifier).
Edit: How to create a valid connection string:
Look at this answer here: How to get the connection String from a database

Can connect mysql database via navicate but cant from c# application

here is all info.
Step 1
Step 2- Error Msg
Step 3- connection String
I have tried without using port number but the problem is same. There is IP restrictions for remote login. but if it is because of IP restriction why am I able to connect with Navicat.
Code of C# where i'm getting error.
As per step 1 it seems the connection has been successfully established, but still you are unable to connect to the specific database. Check the name of the database or confirm that the database exists with the name supplied in the connection string. You can do that even by creating a connection from Navicat. If the database exists you will find it there.
Cheers
Maybe you should invoke mysqlcon.Open() before using mysqlcon.

Create connection string from existing Data connections

I want to connect to Oracle database, but when I manualy write correct connection string, Visual Studio throws me error:
Running transformation: Failed to read database schema - The value's length for key 'data source' exceeds it's limit of '128'.
This connection string works, when I connect via code behind code, but when I add it to config file, it throw this error.
I created correct connection string via Data Connections too, but I dont know any way, how can I automatically create it in config file, for example exporting from data connections to config, or something else..
Thanks.
This error is shown when I put there correct connection string...

Servicestack OrmLite - Execute as User/Impersonation

I am using Servicestack OrmLite as a data layer for my application (.NET C# 3.5/SQL Server).
One of the design requirements (It isn't greenfield, so it is mandatory) is to have commands executed as a particular user which has a schema attached on the SQL server side.
After creating the DbContext with OpenDbConnection() I send an Execute as User command to SQL server so that they are executing with the correct login, and they are switched over to the correct schema for that login.
The error I am getting back for selects against that connection later in the process is:
A severe error occurred on the current command. The results, if any, should be discarded.
Thoughts:
Connection pooling is losing the current user command sent to SQL server?
Is there a built in User/schema handler extension to OrmLite that I haven't seen?
RegisterConnection?
Thanks for your input.

Data source for connection string

What connection string should I use if SSMS connects to it using simply machine name, without instance name?
I mean it connects using the following string: PCName
I used to connect using PCName/SQLExpress. I cannot set correct connection string in my app in order to connect app to database on this machine.
How can I check what data source I should use? I've checked in Sql Server configuration that server instance named as SQLEXPRESS.
So I tried data source as:
.\SQLEXPRESS
PCName\SQLEXPRESS
.
I'm trying to connect to a service-based database, located in my app folder. So I'm using the following connection string:
data source=PCName;attachdbfilename=|DataDirectory|\spareparts.mdf;integrated security=true;user instance=true;multipleactiveresultsets=true;App=EntityFramework;
If SSMS connects via PCName then your application should be able to use Data Source=PCName. However it depends on whether your application is on the same machine as SSMS or not. If on a different machine it might not be able to connect for a variety of reasons. We can't speculate what the problem might be if all you do to describe the issue is "It won't connect" - what does that mean? Do you get an error message? If so, what is it? Make sure:
SQL Browser service is started
TCP/IP is enabled
Add Network=DBMSSOCN; to the connection string
You've also tried the IP address in addition to PCName
Firewall isn't blocking the SQL Server port

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