Database Administrator

Two MySQL services run on one server Two MySQL services run on one server 1. Add a group, add a user to the group, and decompress the package. Groupadd mysql Useradd mysql-g mysql-M-s/sbin/nologin Tar-zxvf

Performance Comparison of massive MySQL Data warehouse receiving Enterprise IM revisedUser chat content should be stored in the database. Generally, JAVA Insert MySQL supports the following methods:1. automatically submit Insert2. transaction commit

Upgrade Oracle 11.2.0.1 to 11.2.0.3 [Note] Generally, production databases do not use similar version 1 or R1 such as Oracle 11.2.0.1. 11.2.0.1 is the basic version, this version has more feature updates than the previous version, and feature

Shell script: monitor whether the MySQL service is normal The general idea is to check whether the MySQL service is normal: Check whether port 3306 is started, ps to check whether the mysqld process is started, and run the command line to log on to

Upgrade MySQL 5.6.23 to MySQL 5.7.9 Upgrade MySQL 5.6.23 to MySQL 5.7.9 New Features of MySQL 5.7.9 I. Security 1.1. The plugin field of mysql. user cannot be blank. The default value is mysql_native_password instead of mysql_old_password. The old

How to troubleshoot ORA-04031 errors when running utlrp. SQL in 11.2.0.4 The last case: The following error occurs when the utlrp. SQL script is compiled at the client site in version 11.2.0.4:ORA-12801: error signaled in parallel query server

Spring + MyBatis multi-data source Switching In actual company projects, it is very likely that there will be a problem: a Java project, but the project involves two databases, the two databases are still on machines with different IP addresses. In

Performance of MariaDB 10.1 and MySQL 5.7 on common commercial hardware When you read my previous article about MariaDB 10.1 GA performance, you may be confused why I haven't mentioned MySQL 5.7 words. There are two reasons: First, MySQL was not GA

Install innobackupex in binary mode Purpose Install innobackupex in binary mode Environment OS: CentOS 6.6 32bit Introduction Official Website: https://www.percona.com/ Https://www.percona.com/downloads/XtraBackup/LATEST/ After opening the webpage,

Using innobackupex to back up a single MySQL database Purpose Using innobackupex to back up a single MySQL database Environment OS: CentOS 6.6 32bit Introduction Official Website: https://www.percona.com/ Https://www.percona.com/downloads/XtraBackup/

Install Oralce 11gR2 database in CentOS 6.6 Environment requirements: Rlwrap-0.42 CentOS release 6.6 (Final) VMware Workstation 11 Linux. x64_11gR2_database_1of2 and linux. x64_11gR2_database_1of2 Download CentOS 6.6 official version Rlwrap:

How to Upgrade Oracle 11g to Orcale 12c Hello everyone. Today we will learn how to Upgrade Oracle 11g to Oracle 12c. Let's get started. Here, I am using the CentOS 7 64-bit Linux release. I suppose you have installed Oracle 11g on your

Analysis on Causes of slow sorting SQL upgrade to MySQL 5.6 Background:After a service DB is upgraded from MySQL 5.5 to MySQL 5.6, the same SQL Execution time has soared from milliseconds to 20 seconds. The SQL text is as follows:Select * from

MySQL5.7 introduction to the JSON type JSON is a lightweight data exchange format, which uses a language-independent text format, similar to XML, but easier to read and write than XML. It is easy for machines to parse and generate, and reduces

Introduction and conversion of MNIST Databases MNIST database Introduction: MNIST is a handwritten digital database with 60000 training samples and 10000 test samples. It is a subset of NIST databases. MNIST database official website is: http://yann.

SQL statement used by MySQL to query duplicate table data MySQL queries duplicate data in a table. For example, to query records with duplicate bar codes in the table, the SQL statement is as follows: SELECT GUIDE_BARCODE FROM checker_barcode

Flash back Version Query Flashback Version Query "Forgetting to back up" is a military rule that impressed the author with the experience of an industry predecessor a few years ago. For DBA, Backup usually refers to "Media Backup", which is a

The SQL statement used to query the data between the nth and NTH rows in the database in SQL SERVER. When writing a program today, You need to generate an SQL statement from the start id to the end id. This function is not required now. In SQL

Use the command line method to log on to SqlPlus. The password contains special characters and special characters of sqlplus. All hits!It's really hard to wait! Oracle 12c. If you want to log on to SQL plus, there is no graphical interface. a

The MySQL command displays all types available for query, and mysql displays all The MySQL command displays all types available for query. Mysql>? Contents; You asked for help about help category: "Contents" For more information, type 'help ',