Database Administrator

Install MySQL using an rpm package in CentOS To install MySQL in CentOS: First, explain MySQL-server-5.0.96-1.glibc23.x86_64.rpm 2. Install the server: [Root @ bkjia mysql] # rpm-ivh MySQL-server-5.1.73-1.glibc23.i386.rpm Display

MySQL master-slave replication principle and Configuration 1 copy Overview The built-in replication function of MySQL is the basis for building large and high-performance applications. This distribution mechanism replicates data from a MySQL host to

Crosscheck backup ORA-19554 A ORA-19554 error occurs when a friend executes crosscheck backup in rman.RMAN> crosscheck backup; Using channel ORA_DISK_1Released channel: ORA_DISK_1RMAN-00571: ==========================================================

[Introduction to database systems] Introduction ---- introduction to database systems (III) and introduction to Database Systems1.2.7 Relational Model Relational model is currently the most important data model.I. Data Structure of the relational

Import large amounts of data into the database, dbf import oracle, csv import oracle, dbfcsv In Excel 07-2003, a worksheet can have a maximum of 65536 rows and a maximum of 256 columns. In Excel 2007 and later versions, a worksheet can have a

Read xml to generate code example, xml code example Read xmlGenerateCorrespondingLua parsing protocol code: # Include # include "tinyxml2.h" # include # include using namespace tinyxml2; using namespace std; std: ofstream file ("readProto. lua ",

Rewrite the oracle wm_contact function script and oraclewm_contact There is a requirement for a recent project to describe consecutive card numbers in one segment, for example, 1, 2, 3, 4, 5, 8, 10, 13, 14, 15, 16, to be displayed as 1-5, 8, 10, 13-1

SQLServer, only when the column list is used and IDENTITY_INSERT is ON, you can specify an explicit value for the ID column in table xx, sqlserveridentity Scenario: if the primary key of the table or one of the columns uses IDENTITY () for

Mysql imports the C ++ implementation and encapsulation of the source database SQL, mysqlsource Many people have had headaches for this issue before: I want to have a database script that can be imported without installing the mysql client, but

An error occurred while uninstalling oracle11g. the file cannot be deleted. The file is in use.When you uninstall oracle11g After the service is stopped, run C: \ myoracle \ think \ product \ 11.2.0 \ dbhome_2 \ deinstall Deinstall. bat in You

MongoDB V3 & V2 lock performance comparison test and lock basic overview, mongodbv31. mongo lock Overview: Features of each version lock: The current Production Version is 2.6.7 [Production Release (2.6.7)] and the Development Version is 3.0.0-rc7

Poor memory Head 21-JAVA database connection pool DBCP, 21-javadbcp Each request requires a link to the database. Creating a connection to the database usually consumes a relatively large amount of resources and takes a long time to create a

Oracle physical storage structure, oracle physical storage The architecture of the Oracle database analyzes the composition, working process, and how the database manages and organizes data from a certain perspective, including the physical storage

Common Transact-SQL functions, and transact-SQL Functions(1) DECLARE:1>:DECLARE @ usid VARCHAR (50), @ usna NVARCHAR (100), @ grna NVARCHAR (100 );2>:DECLARE @ usid VARCHAR (50)DECLARE @ usna NVARCHAR (100)DECLARE @ grna NVARCHAR (100)(2) select 1

Innodb buffer parameters and viewing methods (to be continued), innodbbuffer Buffer parameters: Innodb_buffer_pool_size innodb_buffer size Innodb_buffer_pool_instances innodb_buffer instance count Innodb_old_blocks_pct LRU end mid Point

SQL statement and field quantity when the database calculates the number of different fields Today, fields in Table A are queried, and different types of fields are collected; 1. select count (1) from A where strwhere collects statistics on the

DB2 database backup and recovery, db2 database creation Follow these steps to create a database in the Db2 environment: 1. When su-db2inst is missing, an error will occur; 2. db2 enters the db2 command line mode; 3. create database pb_db on/home/db2

[Leetcode SQL] Employees Earning More Than Their Managers, leetcodeearning TheEmployeeTable holds all employees including their managers. Every employee has an Id, and there is also a column for the manager Id. +----+-------+--------+-----------+|

Recognize databases and databases again I haven't summarized the database for a long time. Let's take a look. What is the database used? Let's discuss it with us. I. Introduction Databases are developed from the file management system and are an

Use principle of group # In v $ log,This article is an original article. For more information, see the source: The CURRENT group # Is 4,5, 6SQL> select group #, status from v $ log; GROUP # STATUS ---------- -------------- 4 INACTIVE 5 CURRENT 6