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Run Apache Sqoop jobs by using .NET SDK for Apache Hadoop in HDInsight

Learn how to use the Azure HDInsight .NET SDK to run Apache Sqoop jobs in HDInsight to import and export between an HDInsight cluster and an Azure SQL Database or SQL Server database.

Förutsättningar

Use Sqoop on HDInsight clusters with the .NET SDK

HDInsight .NET SDK tillhandahåller .NET-klientbibliotek, så att det är enklare att arbeta med HDInsight-kluster från .NET. In this section, you create a C# console application to export the hivesampletable to the Azure SQL Database table that you created from the prerequisites.

Set up

  1. Start Visual Studio and create a C# console application.

  2. Navigate to Tools>NuGet Package Manager>Package Manager Console and run the following command:

    Install-Package Microsoft.Azure.Management.HDInsight.Job

Sqoop export

From Hive to SQL Server. This example exports data from the Hive hivesampletable table to the mobiledata table in SQL Database.

  1. Use the following code in the Program.cs file. Edit the code to set the values for ExistingClusterName, and ExistingClusterPassword.

    using Microsoft.Azure.Management.HDInsight.Job;
using Microsoft.Azure.Management.HDInsight.Job.Models;
using Hyak.Common;

namespace SubmitHDInsightJobDotNet
{
    class Program
    {
        private static HDInsightJobManagementClient _hdiJobManagementClient;

        private const string ExistingClusterName = "<Your HDInsight Cluster Name>";
        private const string ExistingClusterPassword = "<Cluster User Password>";
        private const string ExistingClusterUri = ExistingClusterName + ".azurehdinsight.net";
        private const string ExistingClusterUsername = "admin";

        static void Main(string[] args)
        {
            System.Console.WriteLine("The application is running ...");

            var clusterCredentials = new BasicAuthenticationCloudCredentials { Username = ExistingClusterUsername, Password = ExistingClusterPassword };
            _hdiJobManagementClient = new HDInsightJobManagementClient(ExistingClusterUri, clusterCredentials);

            SubmitSqoopJob();

            System.Console.WriteLine("Press ENTER to continue ...");
            System.Console.ReadLine();
        }

        private static void SubmitSqoopJob()
        {
            var sqlDatabaseServerName = ExistingClusterName + "dbserver";
            var sqlDatabaseLogin = "sqluser";
            var sqlDatabaseLoginPassword = ExistingClusterPassword;
            var sqlDatabaseDatabaseName = ExistingClusterName + "db";

            // Connection string for using Azure SQL Database; Comment if using SQL Server
            var connectionString = "jdbc:sqlserver://" + sqlDatabaseServerName + ".database.windows.net;user=" + sqlDatabaseLogin + "@" + sqlDatabaseServerName + ";password=" + sqlDatabaseLoginPassword + ";database=" + sqlDatabaseDatabaseName;

            // Connection string for using SQL Server; Uncomment if using SQL Server
            // var connectionString = "jdbc:sqlserver://" + sqlDatabaseServerName + ";user=" + sqlDatabaseLogin + ";password=" + sqlDatabaseLoginPassword + ";database=" + sqlDatabaseDatabaseName;

            //sqoop start
            var tableName = "mobiledata";

            var parameters = new SqoopJobSubmissionParameters
            {
                 Command = "export --connect " + connectionString + " --table " + tableName + " --hcatalog-table hivesampletable"
            };
            //sqoop end

            System.Console.WriteLine("Submitting the Sqoop job to the cluster...");
            var response = _hdiJobManagementClient.JobManagement.SubmitSqoopJob(parameters);
            System.Console.WriteLine("Validating that the response is as expected...");
            System.Console.WriteLine("Response status code is " + response.StatusCode);
            System.Console.WriteLine("Validating the response object...");
            System.Console.WriteLine("JobId is " + response.JobSubmissionJsonResponse.Id);
        }
    }
}

  2. To run the program, select the F5 key.

Sqoop import

From SQL Server to Azure Storage. This example is dependent on the above export having been performed. This example imports data from the mobiledata table in SQL Database to the wasb:///tutorials/usesqoop/importeddata directory on the cluster's default Storage Account.

  1. Replace the code above in the //sqoop start //sqoop end block with the following code:

    var tableName = "mobiledata";
var exportDir = "/tutorials/usesqoop/importeddata";

var parameters = new SqoopJobSubmissionParameters
{
    Command = "import --connect " + connectionString + " --table " + tableName + " --target-dir " +  exportDir + " --fields-terminated-by \\t --lines-terminated-by \\n -m 1"
};

  2. To run the program, select the F5 key.

Begränsningar

Linux-baserade HDInsight visar följande begränsningar:

  • Bulk export: The Sqoop connector that's used to export data to Microsoft SQL Server or Azure SQL Database doesn't currently support bulk inserts.

  • Batching: By using the -batch switch, Sqoop performs multiple inserts instead of batching the insert operations.

Nästa steg

Nu har du lärt dig hur du använder Sqoop. Mer information finns i: