千家信息网

Hive数据导入HBase的方法有哪些

发表于:2024-09-22 作者:千家信息网编辑
千家信息网最后更新 2024年09月22日,这篇文章主要介绍Hive数据导入HBase的方法有哪些,文中介绍的非常详细,具有一定的参考价值,感兴趣的小伙伴们一定要看完!Hive数据导入到HBase基本有2个方案:1、HBase中建表,然后Hiv
千家信息网最后更新 2024年09月22日Hive数据导入HBase的方法有哪些

这篇文章主要介绍Hive数据导入HBase的方法有哪些,文中介绍的非常详细,具有一定的参考价值,感兴趣的小伙伴们一定要看完!

Hive数据导入到HBase基本有2个方案:

1、HBase中建表,然后Hive中建一个外部表,这样当Hive中写入数据后,HBase中也会同时更新

2、MapReduce读取Hive数据,然后写入(API或者Bulkload)到HBase

1、Hive 外部表

创建hbase表

(1) 建立一个表格classes具有1个列族user

create 'classes','user'

(2) 查看表的构造

hbase(main):005:0> describe 'classes'DESCRIPTION ENABLED 'classes', {NAME => 'user', DATA_BLOCK_ENCODING => 'NONE', BLOOMFILTER => 'ROW', REPLICATION_SCOPE => '0', true  VERSIONS => '1', COMPRESSION => 'NONE', MIN_VERSIONS => '0', TTL => '2147483647', KEEP_DELETED_CELLS => ' false', BLOCKSIZE => '65536', IN_MEMORY => 'false', BLOCKCACHE => 'true'}

(3) 加入2行数据

put 'classes','001','user:name','jack'put 'classes','001','user:age','20'put 'classes','002','user:name','liza'put 'classes','002','user:age','18'

(4) 查看classes中的数据

hbase(main):016:0> scan 'classes'ROW COLUMN+CELL 001 column=user:age, timestamp=1404980824151, value=20 001 column=user:name, timestamp=1404980772073, value=jack 002 column=user:age, timestamp=1404980963764, value=18 002 column=user:name, timestamp=1404980953897, value=liza

(5) 创建外部hive表,查询验证

create external table classes(id int, name string, age int) STORED BY 'org.apache.hadoop.hive.hbase.HBaseStorageHandler' WITH SERDEPROPERTIES ("hbase.columns.mapping" = ":key,user:name,user:age") TBLPROPERTIES("hbase.table.name" = "classes");select * from classes;OK1 jack 202 liza 18

(6)再添加数据到HBase

put 'classes','003','user:age','1820183291839132'hbase(main):025:0> scan 'classes'ROW COLUMN+CELL 001 column=user:age, timestamp=1404980824151, value=20 001 column=user:name, timestamp=1404980772073, value=jack 002 column=user:age, timestamp=1404980963764, value=18 002 column=user:name, timestamp=1404980953897, value=liza 003 column=user:age, timestamp=1404981476497, value=1820183291839132

(7)Hive查询,看看新数据

select * from classes;OK1 jack 202 liza 183 NULL NULL    --这里是null了,因为003没有name,所以补位Null,而age为Null是因为超过最大值

(8)如下作为验证

put 'classes','004','user:name','test'put 'classes','004','user:age','1820183291839112312'  -- 已经超int了hbase(main):030:0> scan 'classes'ROW COLUMN+CELL 001 column=user:age, timestamp=1404980824151, value=20 001 column=user:name, timestamp=1404980772073, value=jack 002 column=user:age, timestamp=1404980963764, value=18 002 column=user:name, timestamp=1404980953897, value=liza 003 column=user:age, timestamp=1404981476497, value=1820183291839132 004 column=user:age, timestamp=1404981558125, value=1820183291839112312 004 column=user:name, timestamp=1404981551508, value=test                   select * from classes;1 jack 202 liza 183 NULL NULL4 test NULL    -- 超int后也认为是nullput 'classes','005','user:age','1231342'hbase(main):034:0* scan 'classes'ROW COLUMN+CELL 001 column=user:age, timestamp=1404980824151, value=20 001 column=user:name, timestamp=1404980772073, value=jack 002 column=user:age, timestamp=1404980963764, value=18 002 column=user:name, timestamp=1404980953897, value=liza 003 column=user:age, timestamp=1404981476497, value=1820183291839132 004 column=user:age, timestamp=1404981558125, value=1820183291839112312 004 column=user:name, timestamp=1404981551508, value=test 005 column=user:age, timestamp=1404981720600, value=1231342   select * from classes;1 jack 202 liza 183 NULL NULL4 test NULL5 NULL 1231342

注意点:

1、hbase中的空cell在hive中会补null

2、hive和hbase中不匹配的字段会补null

3、Bytes类型的数据,建hive表示加#b

http://stackoverflow.com/questions/12909118/number-type-value-in-hbase-not-recognized-by-hive

http://www.aboutyun.com/thread-8023-1-1.html

4、HBase CF to hive Map

https://cwiki.apache.org/confluence/display/Hive/HBaseIntegration

2、MapReduce 写入 HBase

MR写入到HBase有2个常用方法,1是直接调用HBase Api,使用Table 、Put写入;2是通过MR生成HFile,然后Bulkload到HBase,数据量很大的时候推荐使用

注意点:

1、如果需要从hive的路径中读取一些值怎么办

private String reg = "stat_date=(.*?)\\/softid=([\\d]+)/";private String stat_date;private String softid; ------------厦门map函数中写入-------------String filePathString = ((FileSplit) context.getInputSplit()).getPath().toString();///user/hive/warehouse/snapshot.db/stat_all_info/stat_date=20150820/softid=201/000000_0// 解析stat_date 和softidPattern pattern = Pattern.compile(reg);Matcher matcher = pattern.matcher(filePathString);while(matcher.find()){        stat_date = matcher.group(1);        softid = matcher.group(2);}

2、hive中的map和list怎么处理

hive中的分隔符主要有8种,分别是\001-----> \008

默认    ^A    \001,       ^B    \002:       ^C    \003

Hive中保存的Lis,最底层的数据格式为 jerrick, liza, tom, jerry , Map的数据格式为 jerrick:23, liza:18, tom:0

所以在MR读入时需要简单处理下,例如map需要: "{"+ mapkey.replace("\002", ",").replace("\003", ":")+"}", 由此再转为JSON, toString后再保存到HBase。

3、简单实例,代码删减很多,仅可参考!

public void map(                                LongWritable key,                                Text value,                                Mapper.Context context) {                                String filePathString = ((FileSplit) context.getInputSplit()).getPath().toString();                                ///user/hive/warehouse/snapshot.db/stat_all_info/stat_date=20150820/softid=201/000000_0                                // 解析stat_date 和softid                                Pattern pattern = Pattern.compile(reg);                                Matcher matcher = pattern.matcher(filePathString);                                while(matcher.find()){                                        stat_date = matcher.group(1);                                        softid = matcher.group(2);                                }                                                                rowMap.put("stat_date", stat_date);                                rowMap.put("softid", softid);                                                                String[] vals = value.toString().split("\001");                                                                try {                                        Configuration conf = context.getConfiguration();                                        String cf = conf.get("hbase.table.cf", HBASE_TABLE_COLUME_FAMILY);                                                                                String arow = rowkey;                                         for(int index=10; index < vals.length; index++){                                                byte[] row = Bytes.toBytes(arow);                                                ImmutableBytesWritable k = new ImmutableBytesWritable(row);                                                KeyValue kv = new KeyValue();                                                if(index == vals.length-1){                                                        //dict need                                                         logger.info("d is :" + vals[index]);                                                        logger.info("d is :" + "{"+vals[index].replace("\002", ",").replace("\003", ":")+"}");                                                                                                                                                                        JSONObject json = new JSONObject("{"+vals[index].replace("\002", ",").replace("\003", ":")+"}");                                                        kv = new KeyValue(row, cf.getBytes(),Bytes.toBytes(valueKeys[index]), Bytes.toBytes(json.toString()));                                                }else{                                                        kv = new KeyValue(row, cf.getBytes(),Bytes.toBytes(valueKeys[index]), Bytes.toBytes(vals[index]));                                                }                                                context.write(k, kv);                                        }                                                                        } catch (Exception e1) {                                        context.getCounter("offile2HBase", "Map ERROR").increment(1);                                        logger.info("map error:" + e1.toString());                                }                                                        context.getCounter("offile2HBase", "Map TOTAL").increment(1);                }        }

4、bulkload

int jobResult = (job.waitForCompletion(true)) ? 0 : 1;logger.info("jobResult=" + jobResult);Boolean bulkloadHfileToHbase = Boolean.valueOf(conf.getBoolean("hbase.table.hfile.bulkload", false));if ((jobResult == 0) && (bulkloadHfileToHbase.booleanValue())) {        LoadIncrementalHFiles loader = new LoadIncrementalHFiles(conf);        loader.doBulkLoad(outputDir, hTable);}

以上是"Hive数据导入HBase的方法有哪些"这篇文章的所有内容,感谢各位的阅读!希望分享的内容对大家有帮助,更多相关知识,欢迎关注行业资讯频道!

0