Database Administrator

Test the hash index and principles of MySQL 1. hash index: (hash index) is implemented based on the hash table. Only queries that precisely match the index column can achieve the effect. For each row of data, the storage engine calculates a hash

SQL Server 2016 improves the Query Optimizer The first two versions of SQL Server mainly improve performance by providing new features, while SQL Server 2016 mainly improves its existing functions. Base Estimator The base estimator is the core of

Install Percona Server using the source code package Install Percona Server using the source code package 1. Download the source code tar package. Https://www.percona.com/downloads/Percona-Server-5.6/Percona-Server-5.6.29-76.2/source/tarball/percona-

Upgrade _ Oracle graphical upgrade (dbca database creation after upgrade)-upgrade 10.2.0.1.0 to 10.2.0.5.0 and dbca10.2.0.5.0 **************************************** ******************************** ************** Original Works are from the blog

Summary of database backup and Restoration Technology of the IT Ninja Turtles, and backup of the Ninja Turtles Database    1. exp/imp (export and import the library and unload the database) 1.1 Basic commands 1. Get help $ Exp help = y $ Imp help =

Summary of Oracle database architecture, oracle Architecture   Oracle DB Architecture An Oracle DB server consists of one Oracle DB and one or more database instances. An instance consists of a memory structure and background processes. Whenever an

[Oracle11g, 8] data dictionary and Character Set, oracle11g Character SetI. Data Dictionary: oracle's data dictionary records the metadata of database management. It is a core file of life and death for databases. 1. Place the data dictionary in the

Kettle series tutorials 1. kettle series tutorialsIntroduction to kettle Kettle is an ETL (Extract, Transform and Load extraction, conversion, and loading) tool. It is frequently used in data warehouse projects. kettle can also be used in the

Repeat the library cache lock wait event in Oracle 11 GB, 11 glibrary From the example below, we can see that re-Compilation of objects in the production database will lead to library cache lock, so we should try to avoid compiling objects during

The most outstanding performance of Oracle RAC clusters is high availability, which mainly includes load balance and failover. These technologies enable single point of failure (spof) to prevent normal access to the database by client applications,

Seven Tips for improving MySQL performance: mysql Performance Original article: 7 keys to better MySQL performanceAuthor: Peter ZaitsevTranslator: Peter Note: As the size and load increase, MySQL performance tends to decline. Remember these

SQL server trigger, stored procedure operation remote database insertion data, solve the existing problems on the server, server trigger I recently created a small project, which is not very complicated. I need to back up some data of a database to

Learning MongoDB 6: MongoDB query (cursor operation, cursor information) (3), mongodb cursorI. Introduction Db. collection. find () can be used to query based on conditions and specify fields returned using the projection operator to omit this

Recently, when sorting out content related to the test environment, students often ask the following terms: Database Name, Instance name, database domain name, Global Database Name, service name, This is a few confusing concepts for many beginners.

SQL Server skills: how to monitor and optimize OLAP Databases It is very important to optimize the performance of online analysis and processing. Fortunately, some tools can help monitor and improve the operation of OLAP databases. The Microsoft

BCP is generally stored in the BIN directory of the installed ASE or Open Client. For ASE earlier than version 12, the bcp directory is $ SYBASE/bin, and for Versions later than Version 12 (including version 12), the directory is $

The deduplication technology can provide a larger backup capacity for longer data retention, continuous verification of backup data, improve the level of data recovery services, and facilitate data disaster tolerance. Duplicate data may be in the

Run the DBV command to check whether the data file contains bad blocks before recovery. dbv file=d:\oracle\oradata\mydb\RONLY.DBF blocksize=8192 You can view the data file number and block number of the bad data block to perform a

If it takes several hours to back up or recover a DB2 database, the backup and recovery solution will be safe in a timely manner. Or an inappropriate solution. Therefore, while considering the security of the backup and recovery solution itself, the

We will start from creating an Oracle user permission table, and then explain the login and other general actions to give you an in-depth understanding of the Oracle user permission table. I. Create Sys; // System Administrator with the highest