通过 C++ 中的 ODBC 连接到 Azure Z9778840A0100CB305C982876BA24 数据库时出现问题

Question

This is my first question on StackOverflow, so please excuse my innocence!

Here's the issue: I'm trying to connect via ODBC on Windows in C++ to an Azure SQL database, but without success as I keep getting the following message:

[IM002] [Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified (0)

I retrieved the connection string from Azure and made sure my IP address is registered in the firewall settings.

Following the example provided by Microsoft, I'm connecting thru:

    _retcode = SQLDriverConnect(
        _hDbc,
        NULL,
        ( SQLCHAR * ) connectionString,
        SQL_NTS,
        NULL,
        0,
        NULL,
        SQL_DRIVER_NOPROMPT );

where connectionString is defined as:

const char * connectionString = "Driver = { ODBC Driver 13 for SQL Server };"
    "Server = tcp:<datasource>.database.windows.net, 1433;"
    "Database = <database>;"
    "Uid = <account>; Pwd = <password>;"
    "Encrypt = yes; TrustServerCertificate = no; Connection Timeout = 30;";

Also, I tried to connect via .NET in C# and it works with the following connection string build:

SqlConnectionStringBuilder builder = new SqlConnectionStringBuilder();
    builder.DataSource = "<datasource>.database.windows.net";
    builder.UserID = "<account>";
    builder.Password = "<password>";
    builder.InitialCatalog = "<datavase>";

I was able to perform the "SELECT @@VERSION" statement with the following result:

Microsoft SQL Azure (RTM) - 12.0.2000.8
    Feb 26 2020 10:26:43
    Copyright (C) 2019 Microsoft Corporation

So what am I doing wrong???

Thank you in advance for your help!

Answer 1

I found the solution, First, I provided the OutConnectionString information to display the working connection string. if any.

       SQLDriverConnect(hDbc,
                     GetDesktopWindow(),
                     pwszConnStr,
                     (SQLSMALLINT)wcslen(pwszConnStr),
                     OutConnectionString,
                     BufferLength,
                     &StringLength2Ptr,
                     SQL_DRIVER_COMPLETE));

Then, I reverted to create a DSN file using the wizard that is launched when no command arguments are provided (in the Microsoft sample).

I managed to provide the right arguments and was able to connect to my Azure SQL database.

I printed the OutConnectionString and here's the result (quite far from what I was expecting):

const char * connectionString = "DRIVER=ODBC Driver 17 for SQL Server;SERVER=<server>.database.windows.net;UID=<account>;PWD=<password>;Trusted_Connection=No;DATABASE=<database>;";

I then inserted the string above directly into my code, this time without a prompt:

    _retcode = SQLDriverConnect(
    _hDbc,
    NULL,
    ( SQLCHAR * ) connectionString,
    strlen( connectionString ),
    NULL,
    0,
    NULL,
    SQL_DRIVER_NOPROMPT );

And it's working!

For reference, here are the links to the official Microsoft documentation:

Connect to SQL Database using C and C++

SQLDriverConnect Function

Connect to an ODBC Data Source (SQL Server Import and Export Wizard)

Windows with C++: Using Databases on Windows Azure