Database Administrator

Use the Oracle analysis function ROW_NUMBER () 1. row_number () over () sorting function: (1) row_number () over () group sorting function: When the row_number () over () function is used, the execution of grouping and sorting in over () is later

Warning Information solution after Redis is started Solutions for Redis-related problems. 1st cases: after we started the Redis server, we will see three warnings. If we didn't see them, it would be good, but I did. If you see it, you cannot ignore

After Redis saves the snapshot, it cannot be written. Today, developers suddenly told me that Redis cannot be written. After entering Redis, I found that this is indeed the case and I cannot execute the set command. The following error is reported: 1

Oracle automatically stops the solution after the listener is started This article describes how to automatically stop an Oracle listener after it is started. For a Linux System After entering the ORACLE system, enter su-oracle Enter the command:

Understanding the undo logs, redo logs, and checkpoints in the database This document describes a database file that stores data. The database content is cached in the memory. The name is db buffer. In an operation, we retrieve the data in a table

Python 3 using PyMySQL to connect to Inception When using PyMySQL to connect to the Inception, a value error occurs when determining the version. The reason is that pymysql is separated by '.', but the version information of Inception

MySQL Case sensitivity: lower_case_table_names & lower_case_file_system MySQL Case sensitivity: lower_case_table_names & lower_case_file_system 〇 lower_case_file_systemThis parameter is used to describe whether the operating system of the data

MongoDB installation tutorial and simple operations in Ubuntu1 MongoDB First, let's start with a simple definition of MangoDB: MongoDB is a distributed file storage-based database. Written in C ++. It is designed to provide scalable,

ORA-28000 the account is locked error Simulation The error message is as follows:OCI-Call Error SQL code 28000, the account is lockedSQL>! Oerr ora 28000.28000,000 00, "the account is locked"// * Cause: The user has entered wrong password

Use pg_basebackup to build a PostgreSQL stream replication Environment This article introduces the high availability of PostgreSQL. Here we will first conduct a stream replication experiment. Environment:OS: [Ha @ node0 ~] $ Uname-Linux node0 2.6.32-

The size of Oracle archived logs is much smaller than that of online logs. Some users may be confused about the size of archived logs smaller than those of online logs:First, check whether your archive log files are compressed:SELECT to_char

Install mysql on mac and mysql on mac Install mysql and check1. Download the dmg installation package from the mysql website2. After the download is complete, double-click the installation package and click Next step. The default setting is standard

With 200 lines of code, you can easily implement a simple blockchain and 200 lines of code. Lauri Hartikka The basic concept of blockchain is simple: a distributed database stores an ever-increasing list, which contains many ordered records. However,

Postgresql fatal error: Reserved connection locations are reserved for Super Users who execute non-replication requests, and postgresql Super Users Recently, database monitoring of the monitoring system is always delayed. An error is reported when

Oracle new features 4-maintenance, upgrade, recovery and data pump, and oracle New Features 1. Contents 1) enhanced table partition maintenance. 2) Database Upgrade and improvement. 3) Restore/restore data files across networks. 4) Data Pump

Note and execute shell commands for Mysql queries. mysql executes shell commands. Mysql query notes 1. when querying mysql, you must add the database prefix before the table. Otherwise, the database is the current database by default (when

SQLHelper in niuyun news publishing system (B/S) and niuyun News Publishing System 1. A brief introduction to the basic knowledge of SQLHelper: SqlHelper is A. NET Framework-based database operation component. The component contains the database

Oracle foreign key cascade deletion and cascade update, oracle key level update Cascading Deletion Oracle has three behaviors: no action (similar to RESTRICT), CASCADE, and set null. The following uses the student-class as an example to describe

Oracle442 application scenarios ---------- basic application scenarios and application scenarios   /// // Basic knowledge //////////////////   Application Scenario 178: the simplest select statement SELECT * FROM Employees; Use Case 179: Specify the

Redis service deployment and redis deployment Web programmer blog: http://blog.csdn.net/thinkercode Install Redis 1. Install Redis [root@localhost ~]# wget http://download.redis.io/releases/redis-3.0.2.tar.gz[root@localhost ~]# tar xzf redis-3.0