How to query user's table information in Oracle
How to query user table information in oracle: 1. Use "SELECT count(*) FROM user_tables" to query the number of tables under the current user; 2. Use "SELECT * FROM user_tables;" to query the tables under the current user .
The operating environment of this tutorial: Windows 10 system, Oracle 11g version, Dell G3 computer.
How oracle queries user’s table information
-- View the current user’s table:
SELECT count(*) FROM user_tables; -- 查看当前用户下有多少张表 SELECT * FROM user_tables; -- 查看当前用户下的表 SELECT * FROM user_tab_comments; -- 查看当前用户下的表,注释等 SELECT * FROM user_col_comments; -- 查看当前用户下的表的列名和注释 SELECT * FROM user_tab_columns; -- 查看当前用户下的表的列名等信息(详细但是没有备注) SELECT t.TABLE_NAME, t.NUM_ROWS FROM user_tables t; -- 查看当前用户下的所有表名及该表含多少数据
-- View all users’ tables:
SELECT * FROM all_tab_comments; -- 查看所有用户的表,注释等 SELECT * FROM all_col_comments; -- 查看所有用户的表的列名和注释 SELECT * FROM all_tab_columns; -- 查看所有用户的表的列名等信息(详细但是没有备注)
- - Query template 1:
SELECT t.table_name, t.comments FROM user_tab_comments t;
-- Query template 2:
SELECT r1, r2, r3, r5 FROM ( SELECT a.table_name r1, a.column_name r2, a.comments r3 FROM user_col_comments a ), ( SELECT t.table_name r4, t.comments r5 FROM user_tab_comments t ) WHERE r4 = r1;
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