Database Administrator

Use MySQL-Proxy for MySQL database read/write splitting Experimental System: CentOS 6.6 _ x86_64Prerequisites: Firewall and selinux are both disabled.Tutorial Description: In this experiment, there are a total of four hosts, with IP addresses

Four full recovery scenarios in archive Mode In data backup and recovery, rman is basically used, but from the internal principle of the database, for media recovery, there are actually two things to do: restore and recover.Restore is a copy similar

Automatic varchar2 and number conversion of pure numbers in Oracle When an association query is used, the fields in the two tables define different types. One field is of the varchar2 type, and the other is of the number type. The content is as

Learning notes on five types of Redis objects When using Redis, we directly access String, List, Hash, and Set objects ), sortedSet. Basic commands include String (get set) List (lpush rpush lpop rpop lrange) Hash (hget hset hlen hgetall) set (sadd

Redis command details Redis command details 1. set setnx setex Set associates the value of the string value with the key. If the key already exists, it overwrites the original one. If it does not exist, it is created. Setnx sets the key value as

Oracle uses parallel pitfalls, and Oracle uses parallel How can we quickly delete tens of millions of data records from tables with 10 million data records? You cannot directly delete the file. The best method is: 1. Use create table 2. Concurrent

Connect jdbc to mysql and jdbcmysql Test.java Import java. SQL. driverManager; import java. SQL. resultSet; import java. SQL. SQLException; import java. SQL. connection; import java. SQL. statement; public class Test {static Connection con; //

Make a little progress every day ---- optimize MySQL SERVER (1) and make a little progress every day1. Optimize MySQL Server 7 background processes Masterthread: refreshes dirty cache pages to data files, performs purge operations, triggers

MySql master-slave replication configuration example A recent study of mysql, from the oracle official website of the latest 5.6 mysql, compressed version. Today, it took me a long time to try the Mysql replication function and share my experiences

Leetcode Database, leetcodedatabase Leetcode Database implemented using oracle analysis functions Question 1: Department Top Three Salaries select a.depart, a.name, a.salaryfrom (select d.name depart, e.name name, rank()over(partition by d.id order

Install MongoDb in Windows and mongodb in windows Installing MongoDb in windows is quite comfortable. The specific steps are as follows:1; MongoDb official website, https://www.mongodb.org, according to the corresponding operating system download

Mysql row-to-column conversion using case when, mysqlcase CREATE TABLEbill( idCHAR (36) not null, customerINT (255) null default null comment 'customer ', shopINT (255) null default null comment 'consumption shop ', moneyDECIMAL () null default

How can I quickly delete duplicate data in mysql? Removing duplicates in mysql is actually a very simple task. Let's look at the following example: Mysql> drop table test;Query OK, 0 rows affected (0.01 sec) Mysql> create table test ( Id INT, Name

JDBC calls stored function stored procedures and jdbc stored proceduresJDBC call Stored ProcedureSteps:1: Use the prepareCall () method of the Connection object to create an instance of the CallableStatement object,When using the prepareCall ()

ORACLE syntax-package, procedure, cursor, and oraclecursorExample of Chen kichao: Packet Specification Create or replace package PACK_WMS_YX IS -- Author: CKZ -- Created: 9:52:29 -- Purpose: synchronize data -- Public type declarations, CURSOR

Summary of MySQL development specifications and usage skills, and mysql development and usage skills1. Naming rules 1. The database name, table name, and field name must be separated by lowercase letters and underscores..A) MySQL has the

Debug stored procedures and oracle debug stored proceduresProblem background N lines of code are written in the stored procedure. As soon as the result is run, an error is reported in the database. So how can we immediately test the village crude

Using excel for data mining (7) ---- filling data from examples, excel Data Mining After configuring the environment, you can use excel for data mining. For environment configuration problems, see:

Beckham _ redis learning goal, Beckham _ redis goalRedis learning objectivesI. About NosqlIi. redis IntroductionIii. Applicable scenarios of redisIv. Learning objectives of redis     I. About Nosql Nosql (Nosql = Not Only SQL) refers to the anti-SQL

Beckham _ redis web management interface tool installation, Beckham _ redisRedisWEB management interface tool InstallationI. OverviewIi. File DownloadIii. Installation Process   I. Overview 1. redis is developed based on C/S. That is to say, as long