Oracle中查询某个表的总字段数，要用SQL语句，或者在PL/SQL里面
Oracle中查询某个表的总字段数，，要用SQL语句，或者在PL/SQL里面
能够查出来指定的那张表的字段数。
下面是通过大致查看：
select tname,count(*) from col group by tname; 此时我就联想到了mysql上面去：直接利用函数来解决：
还有就是利用系统表： 在mysql中想要知道数据库中有多少个库： 在mysql数据库中有多少张表：其实在系统表information_schema中大多的数据库，表啊都会有记录的。所以要好好研究下这张表呢。
Oracle中查询某个表的总字段数，要用SQL语句，或者在PL/SQL里面
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