从每见过的问题，请各位高手帮忙解决！

Question

为什么我用desc 的时候，后面的约束啊，类型都消失了？？？？？？SQL> desc test1
 名称                                                                                                   
 ---------------------------------------------------------------------------------------------------
 D1                                                                                                     
 D2                                                                                                     
 C1                                                                                                     
 C2                                                                                                     

Answer 1

用客户端的工具plsql dev, toad等，先看看是怎么回事

Answer 2

如果字段没有什么异常的话，设置一下linesizeSQL> set linesize 50;
SQL> desc t1;
 名称                    是否为空? 类型
 ----------------------- -------- ----------------
 NAME                    NOT NULL VARCHAR2(1000)
 CREATETIME                       TIMESTAMP(6)
 TC                               VARCHAR2(30)

Answer 3

看那长长的条子，估计是linesize太大的缘故