Operations for Oracle Table TEST01 fields

sql> create table test01     (no number not null,name  varchar (30)); 1. Modify the table name     SQL> alter table test01 rename  to test02; Table altered. Sql> desc test01error:ora-04043: object test01 does not existsql>  desc test02 Name                                        Null?    Type ----------------------------- ------------ -------- ---------------------------- NO                                          not null number name                                                 VARCHAR2 ()    2. Changing table column names   sql> alter table test01 rename column no to  nod; Table altered. sql> desc test01 name                                        Null?    Type ----------------- ------------------------ -------- ---------------------------- NOD                       & nbsp;                not  null number name                                                 VARCHAR2 (30) 3. Modify the Nod field type for table test01 sql> alter table test01 modify nod char; Table altered. sql> desc test01 name                                        Null?    Type ----------------- ------------------------ -------- ---------------------------- NOD                                         not null char (1)  NAME                                                  VARCHAR2 (30) 3. Add a single deptsql>  to table test01 ALTER TABLE TEST01 ADD DEPT VARCHAR2 (100); Table altered. sql> desc test01 name                                        Null?    Type ----------------- ------------------------ -------- ---------------------------- NOD                                         not null char (1)  NAME                                                  VARCHAR2 ()  DEPT                                                  VARCHAR2 (100) 4. Add multiple columns to table test01 Sex,agessql> alter table test01 add    (Sex char (2), aGes number); Table altered. sql> desc test01 name                                        Null?    Type ----------------- ------------------------ -------- ---------------------------- NOD                                         not  null char (1)  NAME                                                 varchar2(+)  DEPT                                                 VARCHAR2 ( SEX )                                                  char (2)  AGES                                                  number5. Add and modify columns for table test01 at the same time Sql> desc test01 name                                        Null?     Type ----------------------------------------- -------- --------------------------- - nod                                         not null char (1)  NAME                                                  VARCHAR2 ()  DEPT                                                 VARCHAR2 ( SEX)                                                   char (2)  AGES                                                  NUMBERSQL> alter table test01 add  (New01 char,new02 char)   2  modify  (nod number,name number,dept  number ,sex numbEr,ages char); Table altered. sql> desc test01 name                                        Null?    Type ----------------- ------------------------ -------- ---------------------------- NOD                                         not  NULL NUMBER NAME                                                 number dept                                                 NUMBER SEX                                                   NUMBER AGES                                                  char (1)  NEW01                                                char (1)  NEW02                                                 char (1)  6.*** table test01 column  sql> alter table  test01 drop column dept cascade constraints;alter table test01  Drop column dept cascade constraints*error at line 1:ora-12988: cannot  drop column from table owned by sys because my watch is a column of tables created under SYS and cannot be ***sys, other users can refer to the   The following commands   table column Sql > alter table scott.test01 drop column under the Scott user  dept cascade constraints; 

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