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COMMENT(5)
NAME
  COMMENT - define or change the comment of an object

SYNOPSIS
  COMMENT ON
  [
    [ DATABASE | INDEX | RULE | SEQUENCE | TABLE | TYPE | VIEW ] object_name |
    COLUMN table_name.column_name |
    AGGREGATE agg_name (agg_type) |
    FUNCTION func_name (arg1, arg2, ...) |
    OPERATOR op (leftoperand_type rightoperand_type) |
    TRIGGER trigger_name ON table_name
  ] IS 'text'

  INPUTS

  object_name, table_name,
       The name of the object to be be commented.

  text The comment to add.

  OUTPUTS

  COMMENT
       Message returned if the table is successfully commented.

DESCRIPTION
  COMMENT stores a comment about a database object.  Comments can be easily
  retrieved with psql's \dd, \d+, or \l+ commands. Other user interfaces to
  retrieve comments can be built atop the same built-in functions that psql
  uses, namely obj_description() and col_description().

  To modify a comment, issue a new COMMENT command for the same object. Only
  one comment string is stored for each object.	 To remove a comment, write
  NULL in place of the text string.  Comments are automatically dropped when
  the object is dropped.

  It should be noted that there is presently no security mechanism for
  comments: any user connected to a database can see all the comments for
  objects in that database (although only superusers can change comments for
  objects that they don't own). Therefore, don't put security-critical
  information in comments.

USAGE
  Comment the table mytable:

  COMMENT ON mytable IS 'This is my table.';

  Some more examples:

  COMMENT ON DATABASE my_database IS 'Development Database';
  COMMENT ON INDEX my_index IS 'Enforces uniqueness on employee id';
  COMMENT ON RULE my_rule IS 'Logs UPDATES of employee records';
  COMMENT ON SEQUENCE my_sequence IS 'Used to generate primary keys';
  COMMENT ON TABLE my_table IS 'Employee Information';
  COMMENT ON TYPE my_type IS 'Complex Number support';
  COMMENT ON VIEW my_view IS 'View of departmental costs';
  COMMENT ON COLUMN my_table.my_field IS 'Employee ID number';
  COMMENT ON AGGREGATE my_aggregate (double precision) IS 'Computes sample variance';
  COMMENT ON FUNCTION my_function (timestamp) IS 'Returns Roman Numeral';
  COMMENT ON OPERATOR ^ (text, text) IS 'Performs intersection of two text';
  COMMENT ON TRIGGER my_trigger ON my_table IS 'Used for R.I.';

COMPATIBILITY
  SQL92

  There is no COMMENT in SQL92.

Index for Section 5

Alphabetical listing for C

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