Oracle建表的时候如何添加注释信息

Oracle建表的时候如何添加注释信息

表创建完成后使用下列命令添加列的注释：
comment on column 表名.字段名 is '注释';表的注释：yang@rac1desc user_col_comments
Name Null? Type
-------------------------- -------- ------------
TABLE_NAME NOT NULL VARCHAr2(30)
COLUMN_NAME NOT NULL VARCHAr2(30)
COMMENTS VARCHAr2(4000)
yang@rac1comment on table tchar is ' 这是一个测试表';
Comment created.
yang@rac1select table_name ,comments from user_tab_comments;
TABLE_NAME COMMENTS
------------------------------ -----------------------
TCHAR 这是一个测试表
表中字段的注释：
yang@rac1desc user_col_comments
Name Null? Type
------------------------ -------- ----------------------------
TABLE_NAME NOT NULL VARCHAr2(30)
COLUMN_NAME NOT NULL VARCHAr2(30)
COMMENTS VARCHAr2(4000)
yang@rac1comment on column tchar.val is ' 测试 来自客户 ';
Comment created.
yang@rac1col comments for a45
yang@rac1select comments from user_col_comments where table_name='TCHAR' and column_name='VAL';COMMENTS
测试 来自客户

1、向现有表添加字段 alter table sch_schoolextinfo add (lastyearthequality varchar2(10)); alter table sch_schoolextinfo add (theorytraincomnum varchar2(10)); 2、添加注释 comment on column sch_schoolextinfo.lastyearthequality is '上年度质量信誉考核情况'; sch_schoolextinfo -------> 表名字 lastyearthequality --------> 字段名