druid - 使用 SQL 接口连接到 druid 时出错

Question

我正在尝试使用 avatica jar 连接到 druid 数据库以下是代码。

String url = "jdbc:avatica:remote:url=http://localhost:8082/druid/v2/sql/avatica";
Properties connectionProperties = new Properties();

try (Connection connection = DriverManager.getConnection(url, connectionProperties))
{
    try (
            final Statement statement = connection.createStatement();
            final ResultSet resultSet = statement.executeQuery("SELECT COUNT(*) as rowcount FROM  wikiticker"))
    {
        while (resultSet.next())
        {
            int count = resultSet.getInt("rowcount");
            System.out.println("Total records:" + count);
        }
        resultSet.close();
    }
}
catch (SQLException e)
{
    e.printStackTrace();
}

我收到以下异常，有人可以告诉我出了什么问题吗？我已将运行时属性设置为启用 sql。

Exception in thread "main" java.lang.RuntimeException: Failed to execute HTTP Request, got HTTP/404
        at org.apache.calcite.avatica.remote.AvaticaCommonsHttpClientImpl.send(AvaticaCommonsHttpClientImpl.java:138)
        at org.apache.calcite.avatica.remote.RemoteService.apply(RemoteService.java:34)
        at org.apache.calcite.avatica.remote.JsonService.apply(JsonService.java:172)
        at org.apache.calcite.avatica.remote.Driver.connect(Driver.java:175)
        at java.sql.DriverManager.getConnection(DriverManager.java:664)
        at java.sql.DriverManager.getConnection(DriverManager.java:208)
        at com.test.druid.sql.Main.main(Main.java:17)

Answer 1

看起来您的代理实例-Ddruid.sql.enabled=true在启动时缺少标志。您可以参考http://druid.io/docs/latest/querying/sql.html了解更多详情。