I. query basic table information
Select
UTC. column_name, UTC. data_type, UTC. data_length, UTC. data_precision,
UTC. data_scale, UTC. nullable, UTC. data_default, UCC. Comments
From
User_tab_columns UTC, user_col_comments UCC
Where
UTC. table_name = UCC. table_name
And UTC. column_name = UCC. column_name
And UTC. table_name = 'onlinexls'
Order
Column_id
Note: order by column_id indicates that the result is displayed in the order of data structure design.
Ii. query the table's primary key
Select
Col. column_name
From
User_constraints con, user_cons_columns col
Where
Con. constraint_name = col. constraint_name and con. constraint_type = 'P'
And col. table_name = 'onlinexls'
Iii. query table foreign keys
Select
Distinct (UCC. column_name) column_name, rela. table_name, rela. column_name column_name1
From
User_constraints UC, user_cons_columns UCC,
(Select t2.table _ name, t2.column _ name, t1.r _ constraint_name from Region T1, user_cons_columns T2 where t1.r _ constraint_name = t2.constraint _ name and t1.table _ name = 'onlinexls') rela
Where
UC. constraint_name = UCC. constraint_name
And UC. r_constraint_name = rela. r_constraint_name
And UC. table_name = 'onlinexls'