Oracle常用语句

-- Create table
create table table_name
(
  column1 VARCHAR2(4),
  column2 VARCHAR2(18),
  column3 VARCHAR2(1),
  column4   NUMBER
);

-- Add comments to the table 
comment on table table_name
  is 'table_name的注释';
-- Add comments to the columns 
comment on column table_name.column1
  is 'column1的注释';
comment on column table_name.column2
  is 'column2的注释';
comment on column table_name.column3
  is 'column3的注释';
comment on column table_name.column4
  is 'column4的注释';

-- Create/Recreate primary, unique and foreign key constraints 
alter table table_name
  add constraint table_name primary key (column1);

-- Insert values
insert into table_name (column1,column2,column3,column4) 
values('value1','value2','value3','value4');

-- 给table_name增加一列column5并插入值
alter table table_name add(column5 VARCHAR2(4));  
comment on column table_name.column5 is 'column5的注释';
update table_name set column5 = 'value5';

-- 设置联合主键
alter table table_name drop primary key;
alter table table_name add primary key(column1, column2,column5,column6);