MySQL中查询所有数据库名和表名
查询所有数据库
<span style="font-size: 14px;">show databases;<br/></span>
查询指定数据库中所有表名
<span style="font-size: 14px;">select table_name from information_schema.tables where table_schema='database_name' and table_type='base table';<br/></span>
查询指定表中的所有字段名
<span style="font-size: 14px;">select column_name from information_schema.columns where table_schema='database_name' and table_name='table_name';<br/></span>
查询指定表中的所有字段名和字段类型
<span style="font-size: 14px;">select column_name,data_type from information_schema.columns where table_schema='database_name' and table_name='table_name';<br/></span>
SQLServer中查询所有数据库名和表名
查询所有数据库
<span style="font-size: 14px;">select * from sysdatabases;<br/></span>
查询当前数据库中所有表名
<span style="font-size: 14px;">select * from sysobjects where xtype='U';<br/>xtype='U':表示所有用户表,xtype='S':表示所有系统表。<br/></span>
查询指定表中的所有字段名
<span style="font-size: 14px;">select name from syscolumns where id=Object_Id('table_name');<br/></span>
查询指定表中的所有字段名和字段类型
<span style="font-size: 14px;">select sc.name,st.name from syscolumns sc,systypes st where sc.xtype=st.xtype and sc.id in(select id from sysobjects where xtype='U' and name='table_name');<br/></span>
Oracle中查询所有数据库名和表名
查询所有数据库
由于Oralce没有库名,只有表空间,所以Oracle没有提供数据库名称查询支持,只提供了表空间名称查询。
<span style="font-size: 14px;">select * from v$tablespace;--查询表空间(需要一定权限)<br/></span>
查询当前数据库中所有表名
<span style="font-size: 14px;">select * from user_tables;<br/></span>
查询指定表中的所有字段名
<span style="font-size: 14px;">select column_name from user_tab_columns where table_name = 'table_name';<br/></span>
查询指定表中的所有字段名和字段类型
<span style="font-size: 14px;">select column_name, data_type from user_tab_columns where table_name = 'table_name';<br/></span>
更多相关教程请访问 MySQL视频教程

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