Oracle data dictionary를 이용한 테이블의 컬럼 정의 SQL

SELECT a.column_name,
         c.comments AS column_name_ko,
         CASE
            WHEN data_type = 'VARCHAR2' THEN 'VC2'
            WHEN data_type = 'NUMBER' THEN 'NUM'
            ELSE data_type
         END
         || '(' || data_length || ')' AS TYPE,
         b.key,
         nullable,
         data_default AS defalut,
         c.comments
    FROM cols a
         LEFT OUTER JOIN (  SELECT table_name, COLUMN_NAME, 'PK' AS KEY
                              FROM ALL_CONS_COLUMNS
                             WHERE CONSTRAINT_NAME IN
                                      (SELECT CONSTRAINT_NAME
                                         FROM ALL_CONSTRAINTS
                                        WHERE CONSTRAINT_TYPE = 'P'
                                              AND table_name = 'EMPLOYEES')   --파라미터
                          ORDER BY TABLE_NAME, POSITION) b
            ON a.table_name = b.table_name AND a.column_name = b.column_name
         LEFT OUTER JOIN (SELECT column_name, comments
                            FROM USER_COL_COMMENTS
                           WHERE table_name = 'EMPLOYEES') c --파라미터
            ON a.column_name = c.column_name
   WHERE a.table_name = 'EMPLOYEES' --파라미터
ORDER BY column_id