Database Administrator

Oracle 11g solutions for exporting empty and small tables Oracle 11g has a new feature. When the table has no data, no segment is allocated to save space. Solution: 1) insert a row and then roll back to generate a segment. This method inserts data

Importance of indexes in MySQL connection queries In MySQL, connection queries are often used to read data from multiple tables. Connection query uses the fields in the two tables that match the connection relationship to establish the association

Install MariaDB on the Ubuntu 14.04 (Trusty) Server The MariaDB database management system is a branch of MySQL. MariaDB strives to become an ideal choice for professional, robust, scalable, and reliable SQL database services. To achieve this goal,

Oracle RMAN archive deletion policy RMAN> show all; Configure archivelog deletion policy to none; By default, the archive deletion policy is not configured in Oracle10g 11g; In this case, how does one Delete archive logs that have not been

Use XtraBackup to back up the MySQL database Xtrabackup is an open source backup tool developed by percona, which is different from ibbackup. Ibbackup is a paid backup tool. In terms of its backup performance, ibbackup is inferior to Xtrabackup.

Step 4 of automated MySQL deployment Step 4 of automated MySQL deployment Preparations First, you need to build ftpserver Yum install vsftpd Service vsftpd start In this way, the ftp service is up. It is simple to use, so no configuration file is

HBase System Architecture HBase is an Apache Hadoop database that provides random and real-time read/write access to large data. HBase aims to store and process large data. HBase is an open-source, distributed, multi-version, column-oriented storage

Hibernate ing mechanism Hibernate ing mechanism Object Relation Mapping (ORM) is a technology designed to solve the mismatch between objects and relational databases. In short, ORM uses metadata that describes the ing between objects, automatically

Centos6, mysql 5.5 configure master \ slave Data Synchronization backup, centos6slave Database A serves as the primary service, and database B serves as the synchronization database (note: the databases on both sides must be one-to-one, or there

Use sqoop to import mysql Data to hadoop and sqoophadoop The installation and configuration of hadoop will not be discussed here.Sqoop installation is also very simple. After sqoop is installed, you can test whether it can be connected to mysql

Very Large Memory and HugePages Series 2-configure Large pages, largehugepages How to configure hugepages on linux Glossary: Memlock-max locked-in-memory address space (KB) 1. Configuration/Etc/security/limits. conf memlock Parameter Memlock is

[Chapter 2. configuration (Setup )],2.1. Engine Files Each node requires some attributes to connect the node to a database and register it with a parent node. These attributes are defined in a file named xxxx. properties, which is placed in the

How to synchronize data from a table by using ricds?1. Create a channel insert into sym_channel(channel_id, processing_order, max_batch_size, enabled, description)values('test', 1, 100000, 1, 'channel test for table test') A channel is a set of one

[Practice] mariadb audit and mariadb Audit --- Create the directory mkdir/usr/local/mysql/mysql_logs/auditlogchown mysql: mysql/usr/local/mysql/mysql_logs/auditlog/-- 2. INSTALL the audit plug-in show global variables like 'plugin _ dir'; INSTALL

A deep understanding of oracle transaction isolation and an in-depth understanding of oracle transactionsIn Oracle relational database, let's look at the following question:A transaction: select from T where id> 10 and id Transaction B: update T

PostgreSQL quick creation of empty table TIPS, postgresql empty table tipsMySQL has an excellent Syntax "create table... like", which allows you to quickly copy a table and create its copy. PostgreSQL also has similar syntax and is more flexible,

Use of Mongodb underlying java driver framework tools and mongodb toolsTo use MongoDB, you must properly design the document structure to meet specific requirements. For example, if a document is randomly selected and skip is used to skip a random

Configure and modify CDB and PDB parameters in Oracle 12c, 12 cpdb  1. Configure CDB instance Parameters   The instance parameters for configuring CDB are the same as those for normal instances. You can use alter system to set initialization

Note the following when using oracle 11g ASM: 11 gasm 1. Configure at least two data groups (replica groups are used to store data files; fra replica roup is used as the archiving and backup of the flash back area). I/O performance problems are

Mysql yum installation, mysqlyum Reference: https://www.digitalocean.com/community/tutorials/how-to-install-mysql-5-6-from-official-yum-repositories Today, I sorted out the testing machine at the company and tried to install mysql with yum. I