删除用户

drop user username cascade;

创建用户

create user infodomain identified by username

指定权限

grant adb to username

查询这个用户下的表名

select table_name from user_tables;

编码查询

数据库编码
select * from nls_database_parameters where parameter ='NLS_CHARACTERSET';
本地编码
select userenv('language') from dual;
查询所有 nls
select * from nls_database_parameters

查询创建表

create table tablename as select columnname,
columnname from tablename  where 1=2;