Oracle PL/SQL Tutorial/Table/comment

Add comment to a column

SQL>
SQL> create table salgrades
  2  ( grade      NUMBER(2)
  3  , lowerlimit NUMBER(6,2)
  4  , upperlimit NUMBER(6,2)
  5  , bonus      NUMBER(6,2)
  6  ) ;
Table created.
SQL>
SQL>
SQL> comment on column salgrades.lowerlimit
  2  is     "For sales reps only";
Comment created.
SQL>
SQL> drop table salgrades;
Table dropped.
SQL>

Create comment for a table

SQL>
SQL> create table salgrades
  2  ( grade      NUMBER(2)
  3  , lowerlimit NUMBER(6,2)
  4  , upperlimit NUMBER(6,2)
  5  , bonus      NUMBER(6,2)
  6  ) ;
Table created.
SQL>
SQL>
SQL>
SQL> comment on table salgrades
  2  is     "Salary grades and net bonuses";
Comment created.
SQL>
SQL> drop table salgrades;
Table dropped.

Query column comments through user_col_comments

SQL>
SQL> create table salgrades
  2  ( grade      NUMBER(2)
  3  , lowerlimit NUMBER(6,2)
  4  , upperlimit NUMBER(6,2)
  5  , bonus      NUMBER(6,2)
  6  ) ;
Table created.
SQL>
SQL>
SQL> comment on column salgrades.bonus
  2  is     "For sales reps only";
Comment created.
SQL>
SQL>
SQL>
SQL> select comments
  2  from   user_col_comments
  3  where  table_name  = "SALGRADES"
  4  and    column_name = "COMM";
no rows selected
SQL>
SQL> drop table salgrades;
Table dropped.
SQL>
SQL>

Query user_tab_comments to check the table comment

SQL>
SQL> create table salgrades
  2  ( grade      NUMBER(2)
  3  , lowerlimit NUMBER(6,2)
  4  , upperlimit NUMBER(6,2)
  5  , bonus      NUMBER(6,2)
  6  ) ;
Table created.
SQL>
SQL>
SQL> comment on column salgrades.bonus
  2  is     "For sales reps only";
Comment created.
SQL>
SQL>
SQL> select comments
  2  from   user_tab_comments
  3  where  table_name  = "SALGRADES";
COMMENTS
----------------------------------------------------------------------------------------------------

SQL>
SQL> drop table salgrades;
Table dropped.
SQL>