ora 普通数据字典的"数据字典" / ora Case Sensitive

ora 普通数据字典的"数据字典"
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如果我们想查询跟索引有关的数据字典时，可以用下面这条SQL语句:
SQL>select * from dictionary where instr(comments,'index')>0;
SQL> set line 300;
SQL> col table_name for a30;
SQL> col comments for a200;
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如果我们想知道user_indexes（真正表的名字例如table_test）表各字段名称的详细含义，可以用下面这条SQL语句:
SQL>select column_name,comments from dict_columns where table_name='USER_INDEXES';
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当前用户的权限
SQL> select * from user_role_privs;

USERNAME                       GRANTED_ROLE                   ADM DEF OS_
------------------------------ ------------------------------ --- --- ---
EMS_DEMO                       DBA                            NO  YES NO
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当前用户的所有表（where 特定表）:
SQL>select * from user_tables;

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