Database Administrator

MySQL backup tool-mysqlhotcopy Mysqlhotcopy uses lock tables, flush tables and cp or scp to quickly back up the database. it is the fastest way to back up a database or a single table. It is a physical backup, but it can only be used to back up the

Install MySQL 5.6.21 in CentOS 6.5Install MySQL MySQL is the most widely used database in Linux. The version installed using the online yum method lags behind several minor versions on the MySQL website. This section tests and installs the new

Java Oracle Stored Procedure Problems PL/SQL is an extension of Oracle's standard database language. ORACLE has integrated PL/SQL into ORACLE servers and other tools, in recent years, more developers and DBAs have started to use PL/SQL. This article

Notes for Oracle GoldenGate upgrade Oracle GoldenGate is being upgraded recently. refer to the following documents:How To Upgrade Goldengate From 11.2.1.x to 11.2.1.y for Oracle Database (Document ID 1601971.1)This document makes it clear:2. Stop

Mysql optimization practice (explain & Index) and mysql practiceLab environment: 1. SQL tool: Navicat2 and SQL database. Use openstack database as an example. I. mysql index Query Show index from instances Result field

SQL anti-pattern: "fear of unknown", SQL anti-Pattern NULL 1. select A | B from table; If one of the fields A or B is null, the result of A | B is null; 2. Use of NULL (identify the suspended value ): (1) Replace uncertain values (2) Replace a value

Nodejs + mysql 1, nodejsmysql1. Set to create a database package. json {"name":"shopping-cart-example","version":"0.0.1","dependencies":{"express":"4.10.6","express-session":"1.9.3","jade":"1.8.2","body-parser":"1.10.0","mysql":"2.5.4"}} Database

Application of PowerDesigner (1): Application of powerdesigner The conceptual data model is also called the Information Model (Entity-RelationShip, referred to as E-R). It is based on the Entity-link theory and expands this theory. It models

Mysql fuzzy query optimization and mysql fuzzy query First, create an index for the fields to be searched in the database (mysql index is unfamiliar, please refer to here ). Secondly, use the following function for fuzzy search. If the position is

BUG: mysql 5.6 Invalid use of GRANT/REVOKE command breaks replication, revokereplication Bug Description: When the revoke and grant commands are used to revoke the permission, an error occurred while granting the permission (except for syntax errors)

Use of ISNULL function in SQLserver and IFNULL function in Mysql, isnullifnull This article introduces the isnull function in SQL server and ifnull function in mysql, and introduces the specific usage and differences between the two. If you are

InoReader -- webpage cannot be opened, and inoreader cannot. Recently, when using InoReader, I found that the webpage could not be opened. The error message is as follows: other webpages can be opened, but this webpage cannot be opened. Such a page

Oracle performance optimization operation 11: try to match the like clause at the front end. oracle clause Because the like parameter is frequently used, if the like clause can be indexed, the query efficiency will be greatly improved. Example:

Operations between two tables in the T-SQL database, t-SQL database operations -- Modify data in a table based on another table Update Admin_FCOutDt set oLastId = T. contractID from (select crm_contract.contractTopic, crm_contract.contractID from

Common oracle index creation rules, oracle index creation rules 1. The table's primary key and foreign key must have an index; 2. Indexes should be available for tables with more than 300 of the data volume; 3. For tables that are often connected

Combined primary key generation policy in Hibernate, hibernate primary keyI. Configure the joint primary key in xml Design a class separately as the primary key class, such as StudentPK A. Serializable Interface) B. Rewrite equals () and hashCode ()

Oracle clears table data quickly, Oracle clears table dataOracle Quick Clear table dataI. Introduction   Table data deletion usually involves three common commands: truncate, delete, and drop. However, their execution methods, efficiency, and

Common oracle and oracle languages In Oracle development, the client sends SQL statements to the server, the server compiles and executes SQL statements, and returns the execution results to the client. An Oracle SQL statement consists of the

Introduction to Mondrian MDX and mondrianmdx Introduction to Mondrian MDX     MDX (multidimen1_expression) is the language used to construct and query OLAP databases, just as SQL is used to build and operate relational databases. MDX was the first

Oracle continuous data processing example, oracle Data Processing The function described in the following section is to have a table in the Oracle database, which stores continuous time records and a tag bit. Now you need to obtain a result set: