返回結(jié)果 將返回結(jié)果放到spark rdd 例如： JavaSparkContext sc = new JavaSparkContext(conf);
10余年的原陽(yáng)網(wǎng)站建設(shè)經(jīng)驗(yàn)，針對(duì)設(shè)計(jì)、前端、開(kāi)發(fā)、售后、文案、推廣等六對(duì)一服務(wù)，響應(yīng)快，48小時(shí)及時(shí)工作處理。全網(wǎng)整合營(yíng)銷推廣的優(yōu)勢(shì)是能夠根據(jù)用戶設(shè)備顯示端的尺寸不同，自動(dòng)調(diào)整原陽(yáng)建站的顯示方式，使網(wǎng)站能夠適用不同顯示終端，在瀏覽器中調(diào)整網(wǎng)站的寬度，無(wú)論在任何一種瀏覽器上瀏覽網(wǎng)站，都能展現(xiàn)優(yōu)雅布局與設(shè)計(jì)，從而大程度地提升瀏覽體驗(yàn)。創(chuàng)新互聯(lián)從事“原陽(yáng)網(wǎng)站設(shè)計(jì)”,“原陽(yáng)網(wǎng)站推廣”以來(lái)，每個(gè)客戶項(xiàng)目都認(rèn)真落實(shí)執(zhí)行。
可以參照以下代碼來(lái)實(shí)現(xiàn)：
String?sql="show?tables;?select?*?from?test_tb?limit?10";??
ListString?command?=?new?ArrayListString();??
command.add("hive");??
command.add("-e");??
command.add(sql);??
ListString?results?=?new?ArrayListString();??
ProcessBuilder?hiveProcessBuilder?=?new?ProcessBuilder(command);??
hiveProcess?=?hiveProcessBuilder.start();??
BufferedReader?br?=?new?BufferedReader(new?InputStreamReader(??
hiveProcess.getInputStream()));??
String?data?=?null;??
while?((data?=?br.readLine())?!=?null)?{??
results.add(data);??
}
如果你的項(xiàng)目是java項(xiàng)目的話，就需要使用hive提供的java api，如下代碼：
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import org.apache.log4j.Logger;
/**
* Hive的JavaApi
*
* 啟動(dòng)hive的遠(yuǎn)程服務(wù)接口命令行執(zhí)行：hive --service hiveserver /dev/null 2/dev/null
*
* @author 吖大哥
*
*/
public class HiveJdbcCli {
private static String driverName = "org.apache.hadoop.hive.jdbc.HiveDriver";
private static String url = "jdbc:hive://hadoop3:10000/default";
private static String user = "hive";
private static String password = "mysql";
private static String sql = "";
private static ResultSet res;
private static final Logger log = Logger.getLogger(HiveJdbcCli.class);
public static void main(String[] args) {
Connection conn = null;
Statement stmt = null;
try {
conn = getConn();
stmt = conn.createStatement();
// 第一步:存在就先刪除
String tableName = dropTable(stmt);
// 第二步:不存在就創(chuàng)建
createTable(stmt, tableName);
// 第三步:查看創(chuàng)建的表
showTables(stmt, tableName);
// 執(zhí)行describe table操作
describeTables(stmt, tableName);
// 執(zhí)行l(wèi)oad data into table操作
loadData(stmt, tableName);
// 執(zhí)行 select * query 操作
selectData(stmt, tableName);
// 執(zhí)行 regular hive query 統(tǒng)計(jì)操作
countData(stmt, tableName);
} catch (ClassNotFoundException e) {
e.printStackTrace();
log.error(driverName + " not found!", e);
System.exit(1);
} catch (SQLException e) {
e.printStackTrace();
log.error("Connection error!", e);
System.exit(1);
} finally {
try {
if (conn != null) {
conn.close();
conn = null;
}
if (stmt != null) {
stmt.close();
stmt = null;
}
} catch (SQLException e) {
e.printStackTrace();
}
}
}
private static void countData(Statement stmt, String tableName)
throws SQLException {
sql = "select count(1) from " + tableName;
System.out.println("Running:" + sql);
res = stmt.executeQuery(sql);
System.out.println("執(zhí)行“regular hive query”運(yùn)行結(jié)果:");
while (res.next()) {
System.out.println("count ------" + res.getString(1));
}
}
private static void selectData(Statement stmt, String tableName)
throws SQLException {
sql = "select * from " + tableName;
System.out.println("Running:" + sql);
res = stmt.executeQuery(sql);
System.out.println("執(zhí)行 select * query 運(yùn)行結(jié)果:");
while (res.next()) {
System.out.println(res.getInt(1) + "\t" + res.getString(2));
}
}
private static void loadData(Statement stmt, String tableName)
throws SQLException {
String filepath = "/home/hadoop01/data";
sql = "load data local inpath '" + filepath + "' into table "
+ tableName;
System.out.println("Running:" + sql);
res = stmt.executeQuery(sql);
}
private static void describeTables(Statement stmt, String tableName)
throws SQLException {
sql = "describe " + tableName;
System.out.println("Running:" + sql);
res = stmt.executeQuery(sql);
System.out.println("執(zhí)行 describe table 運(yùn)行結(jié)果:");
while (res.next()) {
System.out.println(res.getString(1) + "\t" + res.getString(2));
}
}
private static void showTables(Statement stmt, String tableName)
throws SQLException {
sql = "show tables '" + tableName + "'";
System.out.println("Running:" + sql);
res = stmt.executeQuery(sql);
System.out.println("執(zhí)行 show tables 運(yùn)行結(jié)果:");
if (res.next()) {
System.out.println(res.getString(1));
}
}
private static void createTable(Statement stmt, String tableName)
throws SQLException {
sql = "create table "
+ tableName
+ " (key int, value string) row format delimited fields terminated by '\t'";
stmt.executeQuery(sql);
}
private static String dropTable(Statement stmt) throws SQLException {
// 創(chuàng)建的表名
String tableName = "testHive";
sql = "drop table " + tableName;
stmt.executeQuery(sql);
return tableName;
}
private static Connection getConn() throws ClassNotFoundException,
SQLException {
Class.forName(driverName);
Connection conn = DriverManager.getConnection(url, user, password);
return conn;
}
}
2、JDBC連接的方式，當(dāng)然還有其他的連接方式，比如ODBC等， 這種方式很常用，可以在網(wǎng)上隨便找到，就不再累贅了。不穩(wěn)定，經(jīng)常會(huì)被大數(shù)據(jù)量沖掛，不建議使用。 3、這種方式是直接利用Hive的 Driver class 來(lái)直接連接，感覺(jué)這種方式不通過(guò)JDBC，應(yīng)該速度會(huì)比較快一點(diǎn)（未經(jīng)驗(yàn)證）。我只是在local模式下測(cè)試過(guò)。
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重慶分公司
