oraclealter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> 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.