Oracle 获取表注释和列注释

select table_name from user_tables; //当前用户拥有的表   
select table_name from all_tables; //所有用户的表 
select table_name from dba_tables; //包括系统表 

select  from user_tab_ments; //当前用户拥有表的注释
select  from dba_tab_ments; //全部用户表的注释
select  from all_tab_ments; //全部用户表的注释
dba_tab_ments, all_tab_ments 比 user_tab_ments 要多一个ower列 

select  from user_col_ments;
select  from dba_col_ments;
select  from all_col_ments;