Detailed explanation of ADG three mode switching

Introduction to AGD Data Guard can open the database in a read-only mode, but at this time, the process of data synchronization using logs by Media Recovery stops. If the physical standby database is in the process of recovery, the database cannot open queries, that is, the log application and read-only opening are mutually exclusive (before 1 ...

Posted on Tue, 23 Nov 2021 19:12:22 -0500 by iMiles

Database deletion to Paolu (plastic)

command Start close remote link exit skip start permission modify password \#Start database net start mysql \#close database net stop mysql \#Remote linked database mysql -h Host address -u user name -p User password mysql -u root -stop /* Connecting and disconnecting servers */ mysql -h address -P port -u user name -p password \#Exit dat ...

Posted on Tue, 23 Nov 2021 02:31:40 -0500 by cdrees

The of Java design pattern -- bridging pattern

1. What is bridging mode? Decouple an abstraction from its implementation so that the two can vary independently. Bridge Pattern: decouple abstraction and implementation so that they can change independently. Another explanation is that there are two (or more) independently changing dimensions in a class. We can make these two (or more) ...

Posted on Mon, 22 Nov 2021 21:22:10 -0500 by andrewmcgibbon

ch2 data management

preface Database management is very important. This paper is based on mysql8.0 text Account Management Create a new account create user 'root'@'localhost' identified by '123456'; create user 'root'@'%' identified by '123456'; "localhost" means that the user can only log in locally, and the remote login is "%" Set a ...

Posted on Mon, 22 Nov 2021 10:51:25 -0500 by synical21

Python summary (primary data structure dictionary and collection)

Dictionary and collection Basics What is a dictionary and what is a collection? A dictionary is a set of elements composed of key and value pairing. In Python 3.7 + dictionary, it is determined to be ordered (Note: in 3.6, dictionary order is an implementation detail, which is officially called a language feature in 3.7, so it cannot be 100% g ...

Posted on Mon, 22 Nov 2021 04:30:41 -0500 by horstuff

SQL Server (2019) database -- data query (Introduction to database system, Fifth Edition)

catalogue 1, Textbook example query 1. Query the names of all students and their year of birth 2. The name, year of birth and Department of all students shall be queried, and the Department name shall be expressed in lowercase letters   3. Query the student number of the elective course 4. Query the names and genders of students not ...

Posted on Mon, 22 Nov 2021 04:26:03 -0500 by Phasma Felis

Android S method of capturing various profile s

1. Prepare the environment Here we are talking about our own method: the general idea is to limit all dex. Even if there is no limit, only the default quicken mode is used, Find the place where the compilerFilter is set in the build. All of them have been changed. How much is there (some parts do not need to be modified. You can also refe ...

Posted on Sun, 21 Nov 2021 21:52:02 -0500 by lucy

php development attendance system, OA system, simple version Mysql database design

CREATE TABLE `attendance_cfg` ( `id` int(10) unsigned NOT NULL AUTO_INCREMENT, `company_id` smallint(5) unsigned NOT NULL DEFAULT '0' COMMENT 'Cells ID', `month` char(7) COLLATE utf8mb4_unicode_ci NOT NULL DEFAULT '' COMMENT 'Date: 202111', `status` tinyint(1) unsigned NOT NULL DEFAULT '0' COMMENT 'Status: 0=Enable 1=Deactivate 2=delete ...

Posted on Sun, 21 Nov 2021 02:31:31 -0500 by bsamson

Backup and recovery of MySQL database under Linux

Author: Grey Original address: Backup and recovery of MySQL database under Linux overview Backup modeexplainremarksmysqldumpBy default, only tables, views, and triggers are backed upBy default, stored procedures and events are not backed up, and configuration parameters need to be added. If stored procedures and events need to be backed up, ...

Posted on Sun, 21 Nov 2021 02:27:27 -0500 by dmb

Database Experiment 6

Experiment 6: advanced query of data table Experimental content Note: all the following tables are based on XSKC mode with Experiment 5 Based on database, please use T-SQL statement to perform the following operations: Query the name and student number of the student whose second word in the name is "Xiang", as well as the elective ...

Posted on Sat, 20 Nov 2021 19:11:00 -0500 by hbuchel