使用Hive(JSON文件)将数据插入Hbase

时间:2015-02-05 17:24:53

标签: json hadoop hive hbase

我已经使用hive在hbase中创建了一个表:

hive> CREATE TABLE hbase_table_emp(id int, name string, role string) 
STORED BY 'org.apache.hadoop.hive.hbase.HBaseStorageHandler'
WITH SERDEPROPERTIES ("hbase.columns.mapping" = ":key,cf1:name,cf1:role")
TBLPROPERTIES ("hbase.table.name" = "emp");

并创建另一个表来加载数据:

hive> create table testemp(id int, name string, role string) row format delimited fields terminated by '\t';
hive> load data local inpath '/home/user/sample.txt' into table testemp;

最后将数据插入到hbase表中:

hive> insert overwrite table hbase_table_emp select * from testemp;
hive> select * from hbase_table_emp;
OK
123 Ram     TeamLead
456 Silva   Member
789 Krishna Member
time taken: 0.160 seconds, Fetched: 3 row(s)

这个表在hbase中是这样的:

hbase(main):002:0> scan 'emp'
ROW                   COLUMN+CELL                                               
 123                  column=cf1:name, timestamp=1422540225254, value=Ram       
 123                  column=cf1:role, timestamp=1422540225254, value=TeamLead  
 456                  column=cf1:name, timestamp=1422540225254, value=Silva     
 456                  column=cf1:role, timestamp=1422540225254, value=Member    
 789                  column=cf1:name, timestamp=1422540225254, value=Krishna      
 789                  column=cf1:role, timestamp=1422540225254, value=Member    
3 row(s) in 2.1230 seconds

我可以为JSON文件执行相同的操作:

 {"id": 123, "name": "Ram", "role":"TeamLead"}
 {"id": 456, "name": "Silva", "role":"Member"}
 {"id": 789, "name": "Krishna", "role":"Member"}

并且做:

hive> load data local inpath '/home/user/sample.json' into table testemp;

请帮忙! :)

1 个答案:

答案 0 :(得分:2)

您可以使用get_json_object函数将数据解析为JSON对象。例如,如果使用JSON数据创建临时表:

DROP TABLE IF EXISTS staging;
CREATE TABLE staging (json STRING);
LOAD DATA LOCAL INPATH '/local/path/to/jsonfile' INTO TABLE staging;

然后使用get_json_object提取要加载到表中的属性:

INSERT OVERWRITE TABLE hbase_table_emp SELECT
  get_json_object(json, "$.id") AS id,
  get_json_object(json, "$.name") AS name,
  get_json_object(json, "$.role") AS role
FROM staging;

对此功能进行了更全面的讨论here