使用环境CDH5.16.1

1.建立一个Hive管理Hbase表的外部表

下面是demo:

//切换到hive用户
sudo hive

create EXTERNAL table v2_mdt_grid_date_gh_cgi
(
key String,
cgi String,
gh String,
cnt_cm String,
cnt_ct String,
cnt_cu String,
cnt_nc String,
cnt_over_lap String,
cnt_rsrp_110 String,
cnt_rsrp_110_sinr_3 String,
cnt_rsrq String,
cnt_rsrq_15 String,
cnt_sc String,
cnt_sinr String,
cnt_sinr_0 String,
cnt_sinr_3 String,
over_lap_rate String,
sum_cmrsrp String,
sum_ctrsrp String,
sum_cursrp String,
sum_nc_rsrp String,
sum_rsrq String,
sum_sc_rsrp String,
sum_sinr String
)
row format delimited fields terminated by '|'
STORED BY 'org.apache.hadoop.hive.hbase.HBaseStorageHandler'
WITH SERDEPROPERTIES("hbase.columns.mapping" = 
"
:key,
attr:cgi,
attr:gh,
imm:cnt_cm,
imm:cnt_ct,
imm:cnt_cu,
imm:cnt_nc,
imm:cnt_over_lap,
imm:cnt_rsrp_110,
imm:cnt_rsrp_110_sinr_3,
imm:cnt_rsrq,
imm:cnt_rsrq_15,
imm:cnt_sc,
imm:cnt_sinr,
imm:cnt_sinr_0,
imm:cnt_sinr_3,
imm:over_lap_rate,
imm:sum_cmrsrp,
imm:sum_ctrsrp,
imm:sum_cursrp,
imm:sum_nc_rsrp,
imm:sum_rsrq,
imm:sum_sc_rsrp,
imm:sum_sinr")
TBLPROPERTIES("hbase.table.name" = "v2.mdt.grid.date_gh_cgi");

其中hive表名不能含义".",hive字段与hbase字段一一对应。

ps:

快速获取hbase表字段方法：

hbase shell
//获取所有hbase表
list
//查询某个表key
scan 'v2.mdt.grid.date_gh_cgi',{LIMIT=>1}
//根据key拿到对应的字段
get 'v2.mdt.grid.date_gh_cgi','190701_s00001nks_101179-135'

//如果遇到字段太多可退出执行：
echo "get 'v2.mdt.grid.date_gh_cgi','190701_s00001nks_101179-135'" | hbase shell > /home/xxx.txt

通过编辑器正则去除

2.检查是否创建表成功并且有了hbase表的数据：

sudo hive;
//连接hive
hive

#记得加分页不然后果很严重！！！！！！！！！
select * from v2_mdt_grid_date_gh_cgi limit 10;

在hive查询sql时记得加分页不然后果很严重！！！！！！！！！

3.导出数据到hdfs:

sudo hive;
//连接hive
hive

insert overwrite directory '/data1/output_glj'//导到hdfs那个位置。
row format delimited fields terminated by ','//分隔符 -->hvie默认列分隔符为：‘/001’
select * from v2_mdt_grid_date_gh_cgi limit 100;//（sql语句可以加自己的条件）

4.从HDFS导出数据到本地服务器：

getmerge命令是合并多个hdfs文件成一个

hadoop fs -getmerge /data1/output_glj/ /data1/output/glj_test.txt

参考：https://www.jianshu.com/p/86ff9d7459b7