ALTER(DATABASE|SCHEMA) database_name SET DBPROPERTIES (property_name=property_value,...);ALTER(DATABASE|SCHEMA) database_name SET OWNER [USER|ROLE] user_or_role;ALTER(DATABASE|SCHEMA) database_name SET LOCATION hdfs_path;
eg:
alterdatabase hive_test set dbproperties ("update"="Tom");alterdatabase hive_test set owner user hadoop;
数据库删除
默认是restrict模式,即数据库中存在表是无法删除数据库
若要强制删除数据库,可选择cascade模式
DROP(DATABASE|SCHEMA)[IFEXISTS] database_name [RESTRICT|CASCADE];
eg:
drop databse ifexists hive_test cascade;
CREATETABLE new_key_value_store
ROW FORMAT SERDE "org.apache.hadoop.hive.serde2.columnar.ColumnarSerDe"
STORED AS RCFile
ASSELECT(key%1024) new_key, concat(key,value) key_value_pair
FROM key_value_store
SORT BY new_key, key_value_pair;
- like建表
CREATE[TEMPORARY][EXTERNAL]TABLE[IFNOTEXISTS][db_name.]table_name
LIKE existing_table_or_view_name
[LOCATION hdfs_path];
CREATE EXTERNAL TABLE page_view(
viewTime INT, userid BIGINT,
page_url STRING, referrer_url STRING,
ip STRING COMMENT'IP Address of the User',
country STRING COMMENT'country of origination')COMMENT'This is the staging page view table'ROW FORMAT DELIMITED FIELDSTERMINATEDBY'\054'
STORED AS TEXTFILE
LOCATION '<hdfs_location>';
- 分区表
CREATETABLE page_view(viewTime INT, userid BIGINT,
page_url STRING, referrer_url STRING,
ip STRING COMMENT'IP Address of the User')COMMENT'This is the page view table'
PARTITIONED BY(dt STRING, country STRING)
STORED AS SEQUENCEFILE;
- 分桶表
CREATETABLE page_view(viewTime INT, userid BIGINT,
page_url STRING, referrer_url STRING,
ip STRING COMMENT'IP Address of the User')COMMENT'This is the page view table'
PARTITIONED BY(dt STRING, country STRING)CLUSTEREDBY(userid) SORTED BY(viewTime)INTO32 BUCKETS
ROW FORMAT DELIMITED
FIELDSTERMINATEDBY'\001'
COLLECTION ITEMS TERMINATEDBY'\002'
MAP KEYSTERMINATEDBY'\003'
STORED AS SEQUENCEFILE;