怎样从oracle数据库中读取表的字段和字段的属性？？？？

Question

select * from ALL_TAB_COLUMNS；

Answer 1

SQL> col tname format a10
SQL> col cname format a15
SQL> col coltype format a15
SQL> select tname,cname,coltype,width from col where tname='TT';TNAME      CNAME           COLTYPE              WIDTH
---------- --------------- --------------- ----------
TT         COL             NUMBER                  22已用时间:  00: 00: 00.50
SQL> select tname,cname,coltype,width from col where tname='DEPT';TNAME      CNAME           COLTYPE              WIDTH
---------- --------------- --------------- ----------
DEPT       DEPTNO          NUMBER                  22
DEPT       DNAME           VARCHAR2                14
DEPT       LOC             VARCHAR2                13已用时间:  00: 00: 00.40
SQL> desc tt
 名称                                      空?      类型
 ----------------------------------------- -------- ------------------
 COL                                                NUMBERSQL> desc dept;
 名称                                      空?      类型
 ----------------------------------------- -------- ------------------
 DEPTNO                                    NOT NULL NUMBER(2)
 DNAME                                              VARCHAR2(14)
 LOC                                                VARCHAR2(13)SQL>