for read only

Reason: A period of time has been to the leadership, the database although one hours back up, but still very dangerous, if the MySQL server suddenly down, or disk failure, not only the MySQL site will be a great threat, and even if the recovery of

First, common tools:Recovery Manager:rman can only perform hot sparing (mount or open state)Oracle Secure BackupUser-managed Backup: CP/DD [if=/of=/blocksize=]Ii. Name of RmanThe Rman name does not allow duplication, and%u is definitely not

BIND and REBIND options for packages and plansThere is several options you can use for binding or rebinding plans and packages. Some of the options is common for both bind and rebind, and for both plans and packages.Defaults:ThedefaultFor a option

The principle of  1 and Dataguard is dataguard by establishing a primary and standby group to establish its reference relationship. Once  standby is created, Dataguard passes the redo of the primary database (PRIMARY) to the standby database and

A recent stress test in a project has encountered a deadlock problem with the database, in short, the following code causes a deadlock at the SERIALIZABLE isolation level: 1234567891011121314 SELECT@findCount=COUNT(id)

1.1. Definition and characteristics of thingsA transaction is a unit of work that consists of a set of SQL statements that manipulate a database, in which all operations succeed at the same time or fail at the same time. Things have the following

Dirty Read, Phantom Read, and non-repeatable READ + transaction ISOLATION level 1. Dirty read: Dirty read refers to when a transaction is accessing the data, and the data has been modified, and this modification has not been committed to the

The Randomaccessfile class is a Java class that can read and write randomly, and can dynamically move pointers for Random writesConstructor information:Main method: If you write on the position where the Seek method is set, the content on the

Database reading and writing separation technology is mainly to the database of read operations and write operations separated, the main benefits are the following points:1. Increase redundancy;2. Increase the processing capacity of the machine;3.

Views ViewA view is one of the objects of a database. A view is also called a virtual table, which is essentially a SELECT statement.The result set of a SELECT statement is given a name that is the name of the view.Role:1. Complex queries can be

1. Preface-"This T-SQL programming is based on the SQL Server development environment-"keywords: t-SQL programming; cursors; views and indexes2. T-SQL Programming basics-"identifier: Regular identifiers must be in kanji, letters, underscores _, @,

A: Preface Spring has two versions of XML configuration and annotations, and I personally like the use of annotations, quite enthusiastic about spring boot! For spring, the core is the IOC container, which is plainly the object (Bean) you

Description: This experiment is configured with Cenos6.6 and MySQL5.6.35 as an exampleFirst, compile and install MySQL1, to avoid problems during the installation process, first install the system dependency packageYum Install Apr autoconf automake

8.1 Creating CursorsSyntax format:DECLARE cursor name [insensitive] Cursor[local | global][forward_only | scroll][Static | keyset | dynamic |fast_forward][Read_Only | scroll_locks | optimistic][Type_warning]For SQL statements[for [Read Only | update]

Three recovery models for SQL SERVER 2005: simple (Sample), full, high-volume (bulk_logged)Full Backup modelFull backup mode is the minimum risk of data loss when data file corruption occurs. If a database is in this mode, all operations are fully

Here are some notes from the 2013 when looking at the Oracle Concept Manual, which is now organized as follows (possibly repeating the contents of some other articles):20,131,012 weeks six Oracle Concept manual Chinese version 4th chapter

SELECT DBT. database_id, Db_name (DBT). database_id) ' database name ', DBT. transaction_id, At.name, at. Transaction_begin_time, case at. Transaction_type when 1 Then ' read/write Transaction ' When 2 Then ' read-only transaction ' when

Performance Comparison:data Access TechniquesPriya DhawanMicrosoft Developer NetworkJanuary 2002Original link: https://msdn.microsoft.com/en-us/library/ms978388.aspxSummary: In a typical application environment, compare the performance performance

Article Source: http://blog.csdn.net/msoso_______1988/article/details/9248535In DB2, there are four isolation levels: Rs,rr,cs,ur. Below are some descriptions of four isolation levels, along with the results of individual tests. Isolation level is

Declare @_stunum nvarchar( -)Declare @_age int--cursor processing objects are each piece of data in the result set and can be manipulated for each piece of dataDeclareCur_stucursor for --declaring CursorsSelectStunum,age fromStudents--for Read only-