导出SQL运行结果的方法总结
private static final String accessId = "userAccessId"; private static final String accessKey = "userAccessKey"; private static final String endPoint = "http://service.odps.aliyun.com/api"; private static final String project = "userProject"; private static final String sql = "userSQL"; private static final String table = "Tmp_" + UUID.randomUUID().toString().replace("-", "_");//其实也就是随便找了个随机字符串作为临时表的名字private static final Odps odps = getOdps(); public static void main(String[] args) {
System.out.println(table);
runSql();
tunnel();
} /*
* 把SQLTask的结果下载过来
* */
private static void tunnel() {
TableTunnel tunnel = new TableTunnel(odps); try {
DownloadSession downloadSession = tunnel.createDownloadSession( project, table);
System.out.println("Session Status is : "
+ downloadSession.getStatus().toString()); long count = downloadSession.getRecordCount();
System.out.println("RecordCount is: " + count);
RecordReader recordReader = downloadSession.openRecordReader(0, count);
Record record; while ((record = recordReader.read()) != null) {
consumeRecord(record, downloadSession.getSchema());
}
recordReader.close();
} catch (TunnelException e) {
e.printStackTrace();
} catch (IOException e1) {
e1.printStackTrace();
}
} /*
* 保存这条数据
* 数据量少的话直接打印后拷贝走也是一种取巧的方法。实际场景可以用Java.io写到本地文件，或者写到远端数据等各种目标保存起来。
* */
private static void consumeRecord(Record record, TableSchema schema) {
System.out.println(record.getString("username")+","+record.getBigint("cnt"));
} /*
* 运行SQL，把查询结果保存成临时表，方便后面用Tunnel下载
* 这里保存数据的lifecycle为1天，所以哪怕删除步骤出了问题，也不会太浪费存储空间
* */
private static void runSql() {
Instance i;
StringBuilder sb = new StringBuilder("Create Table ").append(table)
.append(" lifecycle 1 as ").append(sql); try {
System.out.println(sb.toString());
i = SQLTask.run(getOdps(), sb.toString());
i.waitForSuccess();
} catch (OdpsException e) {
e.printStackTrace();
}
} /*
* 初始化MaxCompute(原ODPS)的连接信息
* */
private static Odps getOdps() {
Account account = new AliyunAccount(accessId, accessKey);
Odps odps = new Odps(account);
odps.setEndpoint(endPoint);
odps.setDefaultProject(project); return odps;
}
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