Oracle数据库命令速查手册-约束

1.define constraints as immediate or deferred 
sql> alter session set constraint[s] = immediate/deferred/default; 
set constraint[s] constraint_name/all immediate/deferred; 
2. sql> drop table table_name cascade constraints 
sql> drop tablespace tablespace_name including contents cascade constraints 
3. define constraints while create a table 
sql> create table xay(id number(7) constraint xay_id primary key deferrable 
sql> using index storage(initial 100k next 100k) tablespace indx); 
primary key/unique/references table(column)/check 
4.enable constraints 
sql> alter table xay enable novalidate constraint xay_id; 
5.enable constraints 
sql> alter table xay enable validate constraint xay_id;