这篇BLOG是我很早以前写的,因为现在搬移到CNBLOGS了,经过整理后重新发出来. 工作之前的几年一直都在搞计算机安全/病毒相关的东西(纯学习,不作恶),其中PE文件格式是必须知识.有些PE文件,比如驱动,系统会在加载时对checksum进行校验,确保驱动文件的完整性.关于PE文件如何校验,网上有很多资料可以学习,这里有一篇文章<An Analysis of the Windows PE Checksum Algorithm>是对WINDOWS API CheckSumMappedFile…
This step calculates checksums for one or more fields in the input stream and adds this to the output as a new field. 为数据流输入的列计算校验码,并将输出作为新的一列. wiki中介绍:http://wiki.pentaho.com/display/EAI/Add+a+checksum Option Description Step name Name of the step. …
w https://en.wikipedia.org/wiki/Checksum https://zh.wikipedia.org/wiki/校验和 A checksum is a small-sized datum derived from a block of digital data for the purpose of detecting errors which may have been introduced during its transmission or storage. I…
Quicksum Time Limit: 1000MS Memory Limit: 65536K Total Submissions: 16488 Accepted: 11453 Description A checksum is an algorithm that scans a packet of data and returns a single number. The idea is that if the packet is changed, the checksum will…
You can use and reference the following built-in variables in yum commands and in all Yum configuration files (that is, /etc/yum.conf and all .repo files in the /etc/yum.repos.d/ directory): $releasever You can use this variable to reference the rele…
1, Index An index is a set of data pointers stored on disk associated with a single table. The main advantage is they greatly speed up select, update, and delete statements, as the query optimizer only has to search the index rather than the entire t…
