文档解释ORA-48421:PredicatestringinthecommandmustbesingleordoublequotedCause:ThepredicatestringisnotsingleordoublequotedAction:Putsingleordoublequotesaroundthepredi...

文档解释ORA-38421:attributestringalreadyexistsCause:Anattributewithamatchingname(orform)alreadyexistsintheattributeset.Action:Droptheexistingattributeorchooseadiffe...

http://blog.csdn.net/u012843100/article/details/52384219...

8421码：一种二进制的数字编码形式，用二进制编码的十进制代码。是将十进制的每一位表示为4位的二进制。比如：十进制6转化为8421码后为0110，十进制66转化为8421码后为01100110总结：简单的说，8421编码其实就是用4位二进制数表示一位十进制数计算机知识回顾之8421编码完美解决Window10自动修复后...