• Xiaobai taught himself python (6) Python string (1)


    Series articles: It is very suitable for Xiaobai’s Python learning route Self taught Python by Xiaobai (1) Python tutorial Xiaobai self taught python (2) construction of Python development environment Xiaobai taught himself python (3) basic syntax of Python Self taught Python by Xiaobai (4) Python data type Self taught Python by Xiaobai (5) Python operator […]

  • Be careful with tolower and toupper, and you’ll get your system down


    I don’t know when to start. Many programmers like to use tolower and toupper to achieve string equality comparison that ignores the case mode. Maybe this habit was introduced from other languages. I guess it’s JS. In order not to cause controversy, I mean JS~ 1: Background 1. Tell a story In our order aggregation […]

  • Character, number, date, conversion of Oracle Foundation (3)


    1. Single valued function in string type Lower: all lowercase Upper: convert all to uppercase Substr: intercepting substrings Concat: string concatenation NVL: Handling null values Initcap: uppercase and lowercase Length: string length Note: the dual dummy table satisfies the select syntax structure      select lower(‘sql oracle’) from dual; Select sysdate from dual; / / print the […]

  • Ubuntu14.04 installing Tomcat server


    Talk about tomcat8.0_ 60 in Linux jdk1.8.0_ The pits on 60 Pit 1 When you download welltomcatAfter that, unzip it to/opt/apache-tomcat-x.x/After that, it started interminalStrike in the middle./bin/startup.shYou will encounter the first pit. Tomcat doesn’t print all the information to the terminal. At this time, you don’t know whether the server has been started! Try […]

  • Python learning string built in method


    capitalize()Change the first character of a string to uppercasecasefold()Change all characters of the whole string to lowercasecenter(width)Centers the string and fills the new string of length width with spacescount(sub[, start[, end]])Returns the number of times sub appears in the string. The start and end parameters indicate the range, optional.encode(encoding=’utf-8′, errors=’strict’)Encodes the string in the encoding […]

  • MySQL batch modify the field name to lowercase


    1、 Batch modify the field name to lowercase; Query to get the execution statement to be adjusted; SELECT concat( ‘alter table ‘, TABLE_ NAME, ‘ change column ‘, COLUMN_ NAME, ‘ ‘, LOWER( COLUMN_ NAME ), ‘ ‘, COLUMN_ TYPE, ‘ comment ”, COLUMN_ Comment, ‘;’) as’ modify script ‘from information_ schema.COLUMNS WHERE TABLE_ Schema […]

  • Talking about shell parameter extension from cve-2020-8816


    1. Preface Recently, I came across the article about PI hole < = 4.3.2 Remote Code Execution Vulnerability (cve-2020-8816). The cause of the vulnerability is not very difficult, but the exp constructed in it has aroused my interest. Since PI hole code converts the parameters of command injection into uppercase, shell parameter extension is used […]

  • Common variable naming standard of Beifu TwinCAT programming


    Suggestions on naming rules of common variables Beifu virtual college( https://tr.beckhoff.com.cn/ ) 1. Constant 1 constants are represented in uppercase letters, with the underline “_” Enhance readability. 1 VAR CONSTANT 2 MAX_HEIGHT: REAL := 1234; (* [Pa]*) 3 END_VAR 2. Definition of project content Take a structure as an example. When defining a structure, the […]

  • Ajax common functions;


    <!DOCTYPE html><html><head><meta charset=”UTF-8″><title>Insert title here</title></head><body> <h1>The Jquery ajax</h1> <fieldset> <legend>jquery</legend> <button onclick=”doGet()”>$get(…)</button> <form> Input: < input type = “text” name = “name” > < input type = “button” Onclick = “dopost()” value = submit “>” </form> <span id=”resultId”></span> </fieldset> <! — introduce jQuery package — > <script type=”text/javascript”></script> <script type=”text/javascript”> 1. This is the get […]

  • Group functions and table relations


    Chapter threeGroup functions and table relations String function –Concat concat concatenates two strings select concat(‘abc’,’ABC’) from dual; select ‘abc’||’ABC’ from dual; select concat(first_name,’_’)||last_name con,t.* from EMPLOYEES t; –Initcap returns a string, the first uppercase and the rest lowercase select initcap(email) from EMPLOYEES; –Length returns the length of the string select length(email),t.* from EMPLOYEES t; –Lower […]

  • Xtrareport report stock in order number converted to Chinese capital number


    First of all, take a look at the effect picture of printing the warehouse entry, as follows: The customer requires a total of one line, and the number in capital Chinese is required. How does xtrareport report make the effect of the above figure? Because it is to convert a number into a capital Chinese […]

  • (14) C ා WinForm custom control – Keyboard (1) – hzhcontrols


    Official website http://www.hzhcontrols.com premise Has been in the industry for 7,8 years, has always wanted to do a set of beautiful custom controls, so there is a series of articles. GitHub:https://github.com/kwwwvagaa/NetWinformControl Code cloud: https://gitee.com/kwwwvagaa/net_ winform_ custom_ control.git If you think the writing is OK, please click a star to support it Welcome to discuss: Penguins […]