Database Administrator

Preliminary understanding of MySQL prefix index and index Selectivity Sometimes you need to index long character columns, such as BLOB, TEXT, or long VARCHAR columns. This will make the index very large and cause slow query. In this case, we can use

How to install Oracle 10g on CentOS 6.6 _ x64 The CentOS 6.6 system used in this experiment. The database is Oracle 10 Gb. Centos: CentOS-6.6_X64-bin-DVD1.iso Oracle Database Version: 10201_database_linux_x86_64.cpio.gz To install the Oracle

MongoDB replica set implementation and read/write splitting In the previous article "building an instance in MongoDB master-slave mode", we briefly introduced how to build a master-slave Mongodb server environment. However, Mongodb does not

MySQL Cluster in a MySQL Cluster1. References 2. Introduction MySQL-Cluster is a technology that allows you to deploy "in memory" database clusters in a non-shared system. Without a shared architecture, the system can use cheap hardware without

MongoDB update document Update () method The update () method is used to update an existing document. The syntax format is as follows: db.collection.update( , , { upsert: , multi: , writeConcern: }) Parameter description:

Install MySQL database using a Binary Package 1.1 install MySQL database in Binary Package 1.1.1 preparations before installation (specifications) [Root @ Mysql_server ~] # Mkdir-p/home/zhurui/tools # create a specified toolkit storage path[Root @

PostgreSQL9.5 new features-row-level security and application-level solutions PostgreSQL 9.5 introduces the row-level security policy feature (RLS), which provides fine-grained control beyond the traditional authorization security system in the data

Setup of MySQL/MariaDB Galera cluster in Linux MariaDB Introduction MariaDB is a MySQL Branch maintained by the open-source community. It is developed by MySQL founder Michael Widenius and uses a GPL license. MariaDB is designed to be fully

PostgreSQL -- run Supervisord on Ubuntu in Docker I tried to use the supervisor to start nginx and PostgreSQL on the docker container boot. Use the following Dockerfile and supervisord. conf files. The above application starts, but stops after a

Detailed steps for installing the Postgresql database in Ubuntu: ubuntupostgresql Introduction As we all know, PostgreSQL is a free object-relational database server (Database Management System). It is very easy to install Postgresql In ubuntu. I

Redis-explore Redis and learn basic usage of Redis. Author: Gigi Sayfan time: 2018.8.28Advertisement Redis is a key-value database in the memory. It is free and open-source. It is implemented in C language and runs very fast. Redis is already a

What is the difference between the unique key constraint of SQLServer and the unique index ?, Sqlserver Index I used to want to know what the difference was, but I forgot it because we seldom use the unique key constraint. A few days ago, my

Error code: 1728 Cannot load from mysql. proc. The table is probably uploaded upted, 1728mysql. procError code: 1728 Cannot load from mysql. proc. The table is probably uploaded uptedHttp://bugs.mysql.com/bug.php? Id = 50183The reason is that mysql.

ORA-28001: the password has expired solution, ora-28001expired Oracle prompt error message ORA-28001: the password has expired, due to new features of Oracle11G, the default password expiration limit for Oracle11G User Creation is 180 days (6

Oracle -- Windows cannot start OracleDBConsoleorcl on the local computer. Error Code 1, oracledbconsoleorcl   After the database is installed, it can be started. After the computer is restarted, an error will be reported when it is manually started.

How Does oracle obtain the SQL Execution Plan of the client to optimize the SQL statement? Today is September 25,. I continue to learn about SQL optimization and have written two notes on how to obtain the SQL Execution Plan. Although the notes are

Author's note Because of living money), it has been almost half a year since I switched to work as an electronic product for Apple accessories. After the transfer, my income has indeed increased a lot and my life has indeed benefited a lot, however,

Create a test table in the database. The database version is ORACLE 10.2.0.1.0) and the table name is test in lower case. The script is as follows: Create table test ( Id NUMBER (10 ), Name VARCHAR2 (20 ), Sex VARCHAR (2) ) -- The

In the second article in the SQL Server series, I have mentioned that I want to write historical data. The history here mainly describes the historical data of the database and the SQL Server itself. To be honest, this part of content should be

OLAP options in Oracle9 I Database Release 2 introduce the analysis workspace and truly integrate the relational and multidimensional data types in the same Database. So far, the only way for developers and DBAs to use the analytic workspace is to