ALTER FOREIGN TABLE
Description
Modifies a foreign table.
Precautions
When multi-layer quotation marks are used for sensitive columns (such as password and secret_access_key) in OPTIONS, the semantics is different from that in the scenario where quotation marks are not used. Therefore, sensitive columns are not identified for anonymization.
Syntax
- Set the attributes of a foreign table.
1 2
ALTER FOREIGN TABLE [ IF EXISTS ] table_name OPTIONS ( { [ ADD | SET | DROP ] option ['value']}[, ... ]);
- Set a new owner.
1 2
ALTER FOREIGN TABLE [ IF EXISTS ] tablename OWNER TO new_owner;
- Set foreign table column options.
ALTER FOREIGN TABLE [ IF EXISTS ] table_name ALTER column_name OPTIONS;
Parameters
- table_name
Specifies the name of an existing foreign table to be modified.
Value range: an existing foreign table name.
- OPTIONS
Specifies the options column of a foreign table. By default, the value is SET in range [ ADD | SET | DROP ].
- option
Specifies the name of the option to be modified.
For details about the value range, see Parameters in CREATE FOREIGN TABLE.
- value
Specifies the new value of option.
- new_owner
Specifies the new owner of a foreign table.
- column_name
Specifies the name of an existing column.
Value range: a string. It must comply with the naming convention.
Examples
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 |
-- Create a foreign table. gaussdb=# CREATE SCHEMA tpcds; gaussdb=# CREATE FOREIGN TABLE tpcds.customer_ft ( c_customer_sk integer , c_customer_id char(16) , c_current_cdemo_sk integer , c_current_hdemo_sk integer , c_current_addr_sk integer , c_first_shipto_date_sk integer , c_first_sales_date_sk integer , c_salutation char(10) , c_first_name char(20) , c_last_name char(30) , c_preferred_cust_flag char(1) , c_birth_day integer , c_birth_month integer , c_birth_year integer , c_birth_country varchar(20) , c_login char(13) , c_email_address char(50) , c_last_review_date char(10) ) SERVER gsmpp_server OPTIONS ( location 'gsfs://10.185.179.143:5000/customer1*.dat', FORMAT 'TEXT' , DELIMITER '|', encoding 'utf8', mode 'Normal') READ ONLY; -- Change foreign table attributes and delete the mode option. gaussdb=# ALTER FOREIGN TABLE tpcds.customer_ft options(drop mode); -- Drop the foreign table. gaussdb=# DROP FOREIGN TABLE tpcds.customer_ft; gaussdb=# DROP SCHEMA tpcds CASCADE; |
Helpful Links
Feedback
Was this page helpful?
Provide feedbackThank you very much for your feedback. We will continue working to improve the documentation.See the reply and handling status in My Cloud VOC.
For any further questions, feel free to contact us through the chatbot.
Chatbot