Hive分区，
1、查看分区
Hive> show partitions table_name;
dt=20101101
dt=20101102
....
Time taken: 0.140 seconds, Fetched: 10 row(s)
2、 hive>desc tb partition(dt=20170612)
3.hive> desc extended tb partition(dt=20170612)
可以用这个命令查看有时候建立分区是在特定指定location的。
4、建立分区表
CREATE EXTERNAL TABLE seed_my (col MAP<STRING, STRING>) partitioned by (dt string) ROW FORMAT DELIMITED FIELDS TERMINATED BY ',' COLLECTION ITEMS TERMINATED BY '\t' MAP KEYS TERMINATED BY '|' STORED AS INPUTFORMAT "org.apache.hadoop.mapred.TextInputFormat" OUTPUTFORMAT "org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat" LOCATION 's3://up/seed/myhome';
5、添加分区
ALTER TABLE table_name ADD PARTITION (dt= '$dt') location '$dt';
ALTER TABLE table_name ADD IF NOT EXISTS PARTITION (dt='$dt') LOCATION '/sss/$dt'; //一次添加一个分区
ALTER TABLE table_name ADD PARTITION (dt='$dt', hour='$hour') location '/path/$dt/$hour PARTITION (dt='$dt', hour='$hour') location '/path/$dt/$hour'; //一次添加多个分区
6\删除分区
ALTER TABLE table_name DROP IF EXISTS PARTITION (dt='dt');
ALTER TABLE table_name DROP IF EXISTS PARTITION (dt='dt', hour='$hour');
修改分区
ALTER TABLE table_name PARTITION (dt='$dt') SET LOCATION "$path";
ALTER TABLE table_name PARTITION (dt='$dt') RENAME TO PARTITION (dt='$dt_yyyymmdd’);