oracle alter语句用法

oracle alter语句用法

sql>
sql> create table bar ( n number );

table created.

sql>
sql> alter table bar add c char(1);

table altered.

sql>
sql> drop table bar;

table dropped.

sql>

  
增加一个日期字段

sql>
sql> create table bar ( n number );

table created.

sql>
sql>  alter table bar add d date;

table altered.

sql>
sql>  select object_type, status
  2      from user_objects
  3     where object_name = 'shield'
  4    /

object_type         status
------------------- -------
package             valid
package body        valid

sql>
sql> drop table bar;

table dropped.

sql>

给己有表的增加字段

sql> -- create demo table
sql> create table employee(
  2    id                 varchar2(4 byte)         not null,
  3    first_name         varchar2(10 byte),
  4    last_name          varchar2(10 byte),
  5    start_date         date,
  6    end_date           date,
  7    salary             number(8,2),
  8    city               varchar2(10 byte),
  9    description        varchar2(15 byte)
 10  )
 11  /

table created.