将 Oracle 数据库中所有用户表的表结构导出,并存储到 Excel 表中,存储信息如下图所示:
问题描述:
将 Oracle 数据库中所有用户表的表结构导出,并存储到 Excel 表中,存储信息如下图所示:
SELECT A.TABLE_NAME,A.COMMENTS,B.COLUMN_NAME,B.COMMENTS FROM USER_TAB_COMMENTS a,USER_COL_COMMENTS b WHERE a.table_name = b.table_name
解决方案:
1) 启动 PL/SQL ,应用需要导出表结构的用户登录目标数据库实例
2) New-SQL window 创建查询窗口
3) 在查询窗口中输入以下查询语句:
select t.TABLE_NAME 表名 ,t.COLUMN_ID 序号 ,t.COLUMN_NAME 字段名 ,t.DATA_TYPE 类型 ,t. DATA_LENGTH 长度 ,t.NULLABLE 是否为空
from user_tab_columns t
其中 User_tab_columns 为当前用户表结构信息表。
4) 只想完成后,在查询窗口中点击按钮显示所有记录信息
5) 右键 -copy to Excel ,将查询信息保存到 Excel 中
6) 通过 Excel 中打开保存的查询结果数据,选择数据 - 筛选,,选择不同的表,然后可以取出不同表的表结构
7) 如果在查询过程中选择特定表的表结构则执行以下语句
select t.TABLE_NAME 表名 ,t.COLUMN_ID 序号 ,t.COLUMN_NAME 字段名 ,t.DATA_TYPE 类型 ,t. DATA_LENGTH 长度 ,t.NULLABLE 是否为空
from user_tab_columns t
where TABLE_NAME=’ 表名 ’
注:这里的表名,需要查询的表名替换,比如 User 表则写成: where TABLE_NAME=’User’
经验总结:
1) 数据表 User_tab_columns 中存储了当前用户所有数据表的表结构。
2) 数据表 all_tab_columns 中存储了当前数据库实例中所有数据表的表结构。
3) 数据表 all_tab_columns 和数据表 user_tab_columns 的区别在于表 all_tab_columns 多了一个 owner 字段,用来存储表所属的用户。
通过 PL/SQL 可以将查询结果直接导出到 Excel 文件中。

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