Tag:character set

  • Character type of MySQL

    Time:2020-11-29

    Character type of MySQL Character type MySQLThere are several types of character storage available, but in most cases we only usecharandvarcharThat’s fine. type size purpose CHAR 0 – 255 bytes Fixed length string VARCHAR 0 – 65535 bytes Variable length string TINYBLOB 0 – 255 bytes A binary string of 255 characters or less TINYTEXT […]

  • [glibc mode] Linux local installation and configuration of MySQL server

    Time:2020-11-4

    Download the MySQL glibc package Pre configuration Tar xvf decompress mysql-linux-glibc-x86_ Sixty-four tar.xz To a folder, such as/home/user/my/mysql Create MySQL user: addUser MySQL Change the installation directory holder of Mysql to MySQL:chown -R mysql:mysql /home/user/my/mysql Authorization: Chmod – R 775 / home / user / my / MySQL Create configuration file and edit custom parameters: […]

  • PHP regular matching Chinese

    Time:2020-10-30

    PHP regular matching Chinese @author: CooperZhang Regular matching character set [\ x {4e00} – \ x {9fa5}] matters needing attention: At the end of the regular expression, u should be added/^…$/u 1、 All matches are in Chinese /^[\x{4e00}-\x{9fa5}]+$/u 2、 Match contains Chinese /[\x{4e00}-\x{9fa5}]+/u 3、 Match Chinese and English (including symbols)_) /[\w\x{4e00}-\x{9fa5}]+/u Regular matching Match Chinese […]

  • Summary: by MySQL utf8 coding pit of the bitter lesson

    Time:2020-10-27

    Source: https://blog.liexing.me/2018/… Recently, I encountered several projects that were coded by utf8 of MySQL. I remember the painful lesson of coding problems before. I will record it and warn myself. Once upon a time, I chose utf8 every time I built a library, and I felt that I didn’t know how cool I was than […]

  • Bitcoin wallet address

    Time:2020-10-27

    Bitcoin wallet address The address of the wallet is calculated according to the public key of the wallet. However, the calculation method on different chains is different, and the encoding method is also different. Ethereum uses the hexadecimal code, and eip-55 uses its case to verify the address.The address of bitcoin is encoded by base58check, […]

  • MySQL download and installation

    Time:2020-10-20

    Original link: https://blog.csdn.net/weixin_ 42869365/article/details/83472466 1、 Download Address: https://dev.mysql.com/downloads/mysql/ Currently, the latest version is 8.0. I choose the latest mysql-5.7.24-winx64.zip 2、 Installation There are two types of MySQL installation files. MSI and. Zip. MSI needs to be installed The ZIP format is self decompressing. After decompressing, MySQL can actually use it, but to configure the environment […]

  • Python regular take Chinese characters, number case English

    Time:2020-10-18

    Remove special characters and retain only Chinese, English and numbers import re String = “123I 123456abcdefgabcdff? / ,。 ,.:;:”’;”'[]{}()()《》” print(string) 123I 123456abcdefg abcvdff? / ,。 ,.:;:”’;”'[]{}()()《》 sub_str = re.sub(u”([^\u4e00-\u9fa5\u0030-\u0039\u0041-\u005a\u0061-\u007a])”,””,string) print(sub_str) result: 123I 123456abcdefg abcvdff function explain sub(pattern,repl,string) Replace all matching expressions in the string with repl [^**] Indicates that none of the characters in this […]

  • Checking and modifying Oracle character set

    Time:2020-10-14

    Checking and modifying Oracle character set When deploying the refactored test environment, Oracle database needs to be created. After using DBCA to create the database, the character set of the database itself is not paid attention to, resulting in all subsequent database scripts after the execution of Chinese garbled. The final solution is to clear […]

  • Userenv and NLS of Oracle_ Lang

    Time:2020-10-13

    Userenv and NLS of Oracle_ Lang 1. The most common use of userenv The userenv function returns information about the current session. The following SQL statement can query the database character set of the current session connection select userenv(‘language’) from dual; ofuserenv(‘parameter’)The official website of the return value is as follows Return the language and […]

  • C ා read CSV using LumenWorks.Framework.IO

    Time:2020-9-27

    1. Nuget installation LumenWorks.Framework.IO   Add the help class code as follows: using LumenWorks.Framework.IO.Csv; using System; using System.Collections.Generic; using System.Data; using System.IO; using System.Linq; using System.Text; using System.Threading.Tasks; namespace FlightAirlineCompare.Logic { public class ReaderCsv { public static DataTable CsvToTable(string path, int titleCount) { if (File.Exists(path)) { return ReadCsv(path, titleCount); } else { Throw new exception […]

  • Common commands of MySQL database

    Time:2020-9-22

    The basic SQL statements include select, insert, update, delete, create, drop, grant, revoke, etc     Library operations Create database: create database shujuku;Create database with character set of database;Create database with verification: create database mydb3 character set = utf8 collate utf8_ general_ CI;Display databases: show databases;Delete database: drop database shujuku;Modify the database code: alter databasese […]

  • Mysql database Basics – Basic Commands

    Time:2020-9-9

    At the same time, it is inevitable for the daily work, development and testing of database. In Internet companies, there are many open source product lines, and MySQL is the most important database used by Internet companies. The first three database products of the first echelon have all achieved significant bonus growth in the database […]