在操作数据库时，我们时常需要给数据库中的表名以及字段名添加注释，如果去写comment语句，或者是直接拼出来一条一条去执行，亦或者使用一些可视化工具去添加，都太过于繁琐。

在此背景下，我想到了一个比较方便的、节省成本的方法与大家分享，就是维护一个注释表，然后编写一个存储过程，存储过程中自动拼成一条一条的comment sql语句,然后利用游标去循环执行，效率非常高，而且维护起来也方便，具体操作步骤如下：

1、建注释表

create table TABCOL_COMMENTS

(

TAB_NAME VARCHAR2(500),

TAB_COMMENTS VARCHAR2(500),

COL_NAME VARCHAR2(500),

COL_COMMENTS VARCHAR2(500)

)

tablespace BIGDATA_STG

pctfree 10

initrans 1

maxtrans 255

storage

(

initial 256

next 256

minextents 1

maxextents unlimited

pctincrease 0

);

-- Add comments to the columns

comment on column TABCOL_COMMENTS.TAB_NAME

is '表名';

comment on column TABCOL_COMMENTS.TAB_COMMENTS

is '表注释';

comment on column TABCOL_COMMENTS.COL_NAME

is '字段名';

comment on column TABCOL_COMMENTS.COL_COMMENTS

is '字段注释';

2、编写存储过程

create or replace procedure PORC_COMMENT is

v_log varchar2(1000);

CURSOR CUR_SQL IS

with A as

(select upper(tab.tab_name) as tab_name, tab.tab_comments, upper(tab.col_name) as col_name,tab.col_comments

from tabcol_comments tab),

--字段注释

B as

(SELECT 'comment on column ' || tab_name || '.' || col_name || ' is ''' || col_comments || '''' as sqls

from A),

--表注释

C as

(select'comment on table ' || tab_name || ' is ''' || tab_comments || '''' as sqls

from A),

D as

(select distinct sqls from C)

select sqls from B

union all

select sqls from D;

begin

execute immediate 'truncate table tabcol_comments_log';

for cur_s in CUR_SQL LOOP

insert into tabcol_comments_log (v_log) values(cur_s.sqls);

commit;

execute immediate cur_s.sqls;

end LOOP;

END PORC_COMMENT;