• The ultimate method of Oracle query deadlock and unlock


    After some processes in Oracle are killed, the status is set to “killed”. However, the locked resources are not released for a long time. Sometimes there is no way to do so, so you have to restart the database. Now we provide a way to solve this problem, which is to kill those that cannot […]

  • Unix / Linux shell regular expression syntax explanation with usage


    Almost all important problems need to filter out useful data from useless data. Learn how many UNIX? Command-line utilities use regular expressions to refine.Strangely enough, to this day I can still repeat the classic Saturday morning song “conjunction junction.”. Whether it’s a good thing (watching too much TV) or bad (maybe a harbinger of my […]

  • Talk to CTO 〡 and pingcap CTO Huang Dongxu about the new blue ocean of open source database


    Column introduction “Dialogue CTO” is a new column of geek park. It talks about the development and growth of R & D managers from the perspective of technologists. In this column, Wang Yingqi, the founder and CEO of enterprise level R & D management tool one, is invited as an interviewer. Wang Yingqi once participated […]

  • Using Chmod command to change the usage of file permission in Linux and UNIX


    After using the ls-l command, we can see that there is a string similar to – rwxrwxrwx in front of the file, which represents the permissions of the fileThree groups of three bits R W x represent the readable (R) / writable (W) / executable permission (x) of the owner / group / others respectivelye. […]

  • Summary of several methods for shell to get string length


    Preface In our daily work, string operation is very common in shell scripts, and there are many ways to achieve it. Here are a few possible ways to find strings. Let’s have a look at the detailed introduction. The method is as follows: [method 1]: use ${ා STR} to get the length of the string […]

  • Freedgo design UML: an online drawing tool


    Record an online drawing tool website, which can do beautiful UML design work. Visit freedgo design Click to edit online: make UML tool editing page online

  • The function code of getting UNIX time stamp with vbs


    There is no time function similar to C standard library in VBS. How to get UNIX timestamp? At first glance, it’s simple: Copy codeThe code is as follows: Function UnixTime() UnixTime = DateDiff(“s”, “01/01/1970 00:00:00”, Now()) End Function A very natural way is to only notice “0:00:00 on January 1, 1970” and ignore “coordinated universal […]

  • Comparison table of UNIX / Linux and MS-DOS instructions


    operation Unix/Linux (Bash) Windows(MS-DOS) Example Entry directory cd cd cd /path/to/target Create directory mkdir md mkdir folderName current directory pwd cd pwd Display directory ls dir ls Remove Directory rm del rm -r /path/to/target Print document lp print lp /path/to/file create a file touch touch fileName Copy file cp copy copy fileName fileNameAlias Find file […]

  • Unix / Linux common command line operations


    Introduction: in view of a period of timeMacThe frequency of using terminal operation after computer is increasing day by day. It’s mainly studious. To sort out the following terminal operation commands for the system MacSystem andLIUNXThe system is based onUNIXThe developed ones are basically universal. Now I useMacFocus on common command lines Common operation command […]

  • Windows terminal edge cmder


    In the field of it, most of the time, it is recommendedLinuxOr classUnixOperating system programming,LinuxAs a generation of excellent operating system, it has become the core of IT industry. The conditional big guys all choose to use MAC programming, the best is the terminal experience, andLinuxA completely consistent command line brings a lot of convenience, […]

  • UNIX family tree


    What is the relationship between Mac OS X, FreeBSD, NetBSD, OpenBSD and other operating systems? Wolfram Schneider has sorted out the family tree of UNIX (mainly BSD Series). Is it clear after reading it? The genealogy tree is drawn with ASCII characters, isn’t it geeky? First Edition (V1) | Second Edition (V2) | Third Edition […]

  • Why is C program as solid as a rock?


    November 11, 2008 (single day ~ ~) C language is a special programming language today. Only a very small number of people can really program with C, and a large part of us have their own views on C. Buffer overflow, stack overflow, integer data overflow, C has many well-known defects, which are spread by […]