ALTER TEXT SEARCH DICTIONARY

Function

Modifies the definition of a full-text retrieval dictionary, including its parameters, name, owner, and schema.

Precautions

• ALTER is not supported by predefined dictionaries.
• Only the owner of a dictionary can do ALTER to the dictionary. System administrators have this permission by default.
• After a dictionary is created or modified, any modification to the user-defined dictionary definition file in the directory specified by FilePath will not affect the dictionary in the database. To make such modifications take effect in the dictionary in the database, run the ALTER TEXT SEARCH DICTIONARY statement to update the definition file of the dictionary.

Syntax

• Modify the dictionary definition.

  1 2 3

  ALTER TEXT SEARCH DICTIONARY name ( option [ = value ] [, ... ] );

• Rename a dictionary.

  1	ALTER TEXT SEARCH DICTIONARY name RENAME TO new_name;

• Set the schema of a dictionary.

  1	ALTER TEXT SEARCH DICTIONARY name SET SCHEMA new_schema;

• Change the owner of a dictionary.

  1	ALTER TEXT SEARCH DICTIONARY name OWNER TO new_owner;

Parameter Description

• name

  Specifies the name of an existing dictionary. (If you do not specify a schema name, the dictionary in the current schema will be used.)

  Value range: name of an existing dictionary

• option

  Specifies the name of a parameter to be modified. Each type of dictionaries has a template containing their custom parameters. Parameters function in a way irrelevant to their setting sequence. For details about parameters, see option.

  

  • The TEMPLATE parameter in a dictionary cannot be modified.
  • To specify a dictionary, specify both the dictionary definition file path (FILEPATH) and the file name (the parameter varies based on dictionary types).
  • The name of a dictionary definition file can contain only lowercase letters, digits, and underscores (_).
• value

  Specifies the new value of a parameter. If = and value are omitted, the previous settings of the parameter will be deleted and the default value will be used.

  Value range: valid values defined for the parameter

• new_name

  Specifies the new name of a dictionary.

  Value range: a string, which complies with the identifier naming convention. A value can contain a maximum of 63 characters.

• new_owner

  Specifies the new owner of a dictionary.

  Value range: an existing user name

• new_schema

  Specifies the new schema of a dictionary.

  Value range: an existing schema name

Examples

CREATE TEXT SEARCH DICTIONARY my_dict (
    TEMPLATE = snowball,
    Language = english,
    StopWords = english 
);

Modify the definition of stop words in Snowball dictionaries. Retain the values of other parameters.

Hard-coded or plaintext AK and SK are risky. For security purposes, encrypt your AK and SK and store them in the configuration file or environment variables.

1

ALTER TEXT SEARCH DICTIONARY my_dict ( StopWords = newrussian, FilePath = 'obs://bucket_name/path accesskey=ak secretkey=sk region=rg' );

Modify the Language parameter in Snowball dictionaries and delete the definition of stop words.

1

ALTER TEXT SEARCH DICTIONARY my_dict ( Language = dutch, StopWords );

Update the dictionary definition and do not change any other content.

1

ALTER TEXT SEARCH DICTIONARY my_dict ( dummy );

Helpful Links

CREATE TEXT SEARCH DICTIONARY, DROP TEXT SEARCH DICTIONARY