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This article shows you how to use table and column comments. The content is concise and easy to understand. It will definitely make your eyes shine. I hope you can gain something from the detailed introduction of this article.

-- Add comments to the table

comment on table EMP

is 'Employee';

-- Add comments to the columns

comment on column emp.mgr

is 'Manager';

-- Retrieving Table Comments

SELECT *

FROM user_tab_comments

WHERE table_name = 'EMP';

-- Retrieving Column Comments

SELECT *

FROM user_col_comments

WHERE table_name = 'EMP';

-- delete comments to table, only set the value null

comment on table EMP

is '';

-- delete comments to column, only set the value null

comment on column emp.mgr

is '';

What is the use of comments in tables and columns? Have you learned any knowledge or skills? If you want to learn more skills or enrich your knowledge reserves, please pay attention to the industry information channel.

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