COMMENT ON PROJECTION COLUMN

Adds, revises, or removes a projection column comment.

Adds, revises, or removes a projection column comment. Each object can have one comment. Comments are stored in the system table COMMENTS.

Syntax

COMMENT ON COLUMN [[database.]schema.]projection.column IS {'comment' | NULL}

Parameters

[database.]schema

Database and schema. The default schema is public. If you specify a database, it must be the current database.

projection.column
The name of the projection and column with which to associate the comment.
comment
Specifies the comment text to add. If a comment already exists for this column, this comment overwrites the previous comment.

Comments can be up to 8192 characters in length. If a comment exceeds that limitation, Vertica truncates the comment and alerts the user with a message.

NULL
Removes an existing comment.

Privileges

Non-superuser: object owner

Examples

The following example adds a comment to the customer_name column in the customer_dimension projection:

=> COMMENT ON COLUMN customer_dimension_vmart_node01.customer_name IS 'Last name only';

The following example removes a comment from the customer_name column in the customer_dimension projection:

=> COMMENT ON COLUMN customer_dimension_vmart_node01.customer_name IS NULL;