如何使用 RhinoETL 框架从 SQL 服务器 table 读取数据？

Question

RhinoETL 上的许多示例代码都谈到从 csv 文件加载并插入数据库。如何从 SQL 服务器数据库执行读取并将其行输出到控制台？您有执行简单的 dbread 和批量读取的示例代码吗？

author's blog 显示了一些示例代码，但它似乎不完整，或者我遗漏了什么。

我的非工作代码

public class ReadBuildInfos : ConventionInputCommandOperation
{
    public ReadBuildInfos(ConnectionStringSettings csSettings) : base(csSettings)
    {
        Command = "SELECT Key, Value FROM dbo.BuildInfos WITH (NOLOCK);";
    }

    public override IEnumerable<Row> Execute(IEnumerable<Row> rows)
    {
        foreach (Row row in rows)
        {
            yield return row;
        }
    }
}

Answer 1

直接用Rhino.Etl调试后，发现我犯了2个错误：

ConnectionStringSettings 应该包括 providerName 。 RhinoETL 对此抛出异常，但不知何故我看不到它

    var csString = new ConnectionStringSettings("myConnection2",
        "Server=yourdatabasehere.database.windows.net;Database=MyDbName;User ID=youruser;Password=yourpassword",
        "System.Data.SqlClient"); //I was missing this.
    Register(new ReadBuildInfosConvention(csString));

作者的博客完成了。 Execute 方法不应被覆盖。一个SQLReader就这么简单：

public class ReadBuildInfosConvention : ConventionInputCommandOperation
{
    public ReadBuildInfosConvention(ConnectionStringSettings csSettings) : base(csSettings)
    {
        Command = "SELECT [Key], [Value] FROM BuildInfos WITH (NOLOCK);";
    }
}

因为基础 Execute 方法已经适当地处理了数据库读取

    public override IEnumerable<Row> Execute(IEnumerable<Row> rows)
    {
        using (IDbConnection connection = Use.Connection(ConnectionStringSettings))
        using (IDbTransaction transaction = BeginTransaction(connection))
        {
            using (currentCommand = connection.CreateCommand())
            {
                currentCommand.Transaction = transaction;
                PrepareCommand(currentCommand);
                using (IDataReader reader = currentCommand.ExecuteReader())
                {
                    while (reader.Read())
                    {
                        yield return CreateRowFromReader(reader);
                    }
                }
            }

            if (transaction != null) transaction.Commit();
        }
    }

这是一个有效的 VS solution with logging。

如何使用 RhinoETL 框架从 SQL 服务器 table 读取数据？

How to read from SQL Server table with RhinoETL framework?

c#

sql-server

rhino-etl