：CREATE EXTERNAL TABLE

前提條件

• 叢集的產品系列為湖倉版。

• 叢集的核心版本為3.1.8.0及以上版本。

  說明

  查看湖倉版叢集的核心版本，請執行SELECT adb_version();。如需升級核心版本，請聯絡支援人員。

• 已建立外部資料庫。建立外部資料庫的方法，請參見CREATE EXTERNAL DATABASE。

注意事項

不支援跨帳號建立外表。

OSS外表

文法

CREATE EXTERNAL TABLE [IF NOT EXISTS] table_name
(column_name column_type[, …])
[PARTITIONED BY (column_name column_type[, …])]
ROW FORMAT DELIMITED FIELDS TERMINATED BY ','
STORED AS {TEXTFILE|ORC|PARQUET|JSON|RCFIL|HUDI}
LOCATION 'OSS_LOCATION';
[TBLPROPERTIES (
 'type' = 'cow|mor'
 'auto.create.location' = 'true|false')]

參數說明

樣本

樣本1：建立非分區外表

• 指定檔案儲存體格式為TEXTFILE。

  CREATE EXTERNAL TABLE IF NOT EXISTS adb_external_demo.osstest1
  (id int,
  name string,
  age int,
  city string)
  ROW FORMAT DELIMITED FIELDS TERMINATED BY  ','
  STORED AS TEXTFILE
  LOCATION  'oss://testBucketName/osstest/p1=hangzhou/p2=2023-06-13/data.csv';

• 指定檔案儲存體格式為HUDI。

  CREATE EXTERNAL TABLE IF NOT EXISTS adb_external_demo.osstest2
  (id int,
  name string,
  age int,
  city string)
  STORED AS HUDI
  LOCATION  'oss://testBucketName/osstest/test'
  TBLPROPERTIES ('type' = 'cow');

  重要

  建立Hudi外表時，會自動建立_hoodie_commit_time、_hoodie_commit_seqno、_hoodie_record_key、_hoodie_partition_path和_hoodie_file_name5個固定列。

• 指定檔案儲存體格式為PARQUET。

  CREATE EXTERNAL TABLE IF NOT EXISTS adb_external_demo.osstest3
  (
  A STRUCT < var1:string, var2:int >
  ) 
  STORED AS PARQUET 
  LOCATION 'oss://testBucketName/osstest/Parquet';

樣本2：建立分區外表

CREATE EXTERNAL TABLE IF NOT EXISTS adb_external_demo.osstest4
(id int,
name string,
age int,
city string)
PARTITIONED BY (p2 string)
ROW FORMAT DELIMITED FIELDS TERMINATED BY  ','
STORED AS TEXTFILE
LOCATION  'oss://testBucketName/osstest/p1=hangzhou/';

樣本3：建立多級分區外表

CREATE EXTERNAL TABLE IF NOT EXISTS adb_external_demo.osstest5
(id int,
name string,
age int,
city string)
PARTITIONED BY (p1 string,p2 string)
ROW FORMAT DELIMITED FIELDS TERMINATED BY  ','
STORED AS TEXTFILE
LOCATION  'oss://testBucketName/osstest/';

RDS MySQL外表

文法

CREATE EXTERNAL TABLE [IF NOT EXISTS] table_name
(column_name column_type[, …])
ENGINE='MYSQL'
TABLE_PROPERTIES='{  
	"url":"mysql_vpc_address",  
	"tablename":"mysql_table_name",  
	"username":"mysql_user_name",  
	"password":"mysql_user_password"
	[,"charset":"{gbk|utf8|utf8mb4}"]
  }';

參數說明

樣本

CREATE EXTERNAL TABLE IF NOT EXISTS adb_external_demo.mysqltest (
	id int,
	name varchar(1023),
	age int
 ) ENGINE = 'MYSQL'
 TABLE_PROPERTIES = '{
   "url":"jdbc:mysql://rm-bp1gx6h1tyd04****.mysql.rds.aliyuncs.com:3306/test_adb",
   "tablename":"person",
   "username":"testUserName",
   "password":"testUserPassword",
   "charset":"utf8"
}';

MongoDB外表

文法

CREATE EXTERNAL TABLE [IF NOT EXISTS] table_name
(column_name column_type[, …])
ENGINE='MONGODB'
TABLE_PROPERTIES = '{
	"mapped_name":"table",
  "location":"location",
  "username":"user",
  "password":"password",
}';

參數說明

樣本

CREATE EXTERNAL TABLE adb_external_demo.person (
  id int,
  name string,
  age int
) ENGINE = 'MONGODB' TABLE_PROPERTIES ='{
"mapped_name":"person",
"location":"mongodb://testuser:****@dds-bp113d414bca8****.mongodb.rds.aliyuncs.com:3717,dds-bp113d414bca8****.mongodb.rds.aliyuncs.com:3717/test_mongodb",
"username":"testuser",
"password":"password",
}';

Tablestore外表

文法

CREATE EXTERNAL TABLE [IF NOT EXISTS] table_name
(column_name column_type[, …])
ENGINE='OTS'
TABLE_PROPERTIES = '{
	"mapped_name":"table_name",
	"location":"tablestore_vpc_address"
}';

參數說明

樣本

CREATE EXTERNAL TABLE IF NOT EXISTS adb_external_demo.otstest (
	id int,
	name string,
	age int
) ENGINE = 'OTS' 
TABLE_PROPERTIES = '{
	"mapped_name":"person",
	"location":"https://w0****la.cn-hangzhou.vpc.tablestore.aliyuncs.com"
}';

MaxCompute外表

文法

CREATE EXTERNAL TABLE [IF NOT EXISTS] table_name
(column_name column_type[, …])
ENGINE='ODPS'
TABLE_PROPERTIES='{
	"endpoint":"endpoint",
	"accessid":"accesskey_id",
	"accesskey":"accesskey_secret",
	["partition_column":"partition_column"],
	"project_name":"project_name",
	"table_name":"table_name"
}'; 

參數說明

樣本

CREATE EXTERNAL TABLE IF NOT EXISTS adb_external_demo.mctest (
	id int,
	name varchar(1023),
	age int,
	dt string
) ENGINE='ODPS'
TABLE_PROPERTIES='{
	"accessid":"LTAILd4****",
	"endpoint":"http://service.cn-hangzhou.maxcompute.aliyun.com/api",
	"accesskey":"4A5Q7ZVzcYnWMQPysX****",
	"partition_column":"dt",
	"project_name":"test_adb",
	"table_name":"person"
}';

相關文檔

• OSS外表：通過外表匯入OSS資料至湖倉版。

• RDS MySQL外表：通過外表匯入至湖倉版。

• MongoDB外表：MongoDB資料匯入。

• Tablestore外表：查詢並匯入Tablestore資料。

• MaxCompute外表：通過外表匯入至湖倉版。