oracle 常用系统表

--查看用户下所有的表
select * from user_tables;

--查看用户下所有的表的列属性
select * from USER_TAB_COLUMNS where table_name=upper(\':table_name\');

--查看某表的创建时间
select object_name,created from user_objects where object_name=upper(\':table_name\');

--查看某表的大小
select sum(bytes)/(1024*1024) as "size(M)" from user_segments where segment_name=upper(\':table_name\');

--查看所有视图名称及创建视图的select语句
select view_name,text from user_views;

--查看函数和过程等的源代码
select * from user_source 

--查看表注释
select * from user_tab_comments where table_name=upper(\':table_name\');

--查看表的字段的注释
select * from user_col_comments where table_name=upper(\':table_name\');