DataGuard 12.1 – FastSync and FarSync

From 12c onwards, Data Guard maximum availability supports the use of the noaffirm redo transport parameter. It enables Maximum Availability protection mode at larger distances with less performance impact then before. In “LogXptMode=FASTSYNC” mode, standby database returns receipt acknowledgment to its primary database as soon as redo is received in memory. The standby database does not wait for the Remote File Server (RFS) to write to a standby redo log file.

This is how FastSync set up: Continue reading → DataGuard 12.1 – FastSync and FarSync

MySQL 5.7 – Server Logs

MySQL can write to various types of logs;

    • Error Log – Records diagnostic messages regarding startup, shutdown and abnormal conditions.
      • Windows – host_name.err or errors can also logged to the event viewer
      • Linux – host_name.err or log-error=file_name option to log files.
    • General Query Log – Records all statements that the server receives from clients. The general query logs can be very useful when you suspect an error in a client and want to know exactly what the client sent to mysqld.
      • By default, the general query log is disabled.
      • The global general_log and general_log_file server variables provide runtime control over the general log.
      • Set general_log=0 or OFF to disable the log and 1 or ON to enable it.
      • Set general_log_file=file_name to specify the log file. If a file is already open, it is closed and the new log file is opened. If no file name is given then by default host_name.log is created under data directory.
      • The output is written to any destination specified by –log-output option which can be table, file or None.

Continue reading → MySQL 5.7 – Server Logs

MySQL 5.7 – Installation

MySQL is available for several operating systems. In this blog, I’ll cover windows and Linux only.

For MySQL 5.7, there are multiple installation package formats to choose from when installing MySQL on Windows.

MySQL Installer:  The package has the file name (mysql-installer-community-5.7.21.0.msi or mysql-installer-commercial-5.7.21.0.msi) for community and commercial use. The Installer option will download and apply updates to itself and each of the product installed. MySQL installer can install and manage many other products, including..

  • Application – MySQL workbench, MySQL notifier, MySQL utilities etc..
  • Connectors – MySQL connector/C, C++ , Connector/Python etc…
  • documentation – MySQL Manual (PDF format), samples and examples

Community Edition is further of two type: Web and Full. Continue reading → MySQL 5.7 – Installation

MySQL – Architecture and Components

This Blog will focus on MySQL logical and physical architecture overview. MySQL operates in networked environment using client/server architecture. A MySQL installation has the following major components.

  • MySQL Server
    • is also referred to as mysqld
    • Manage access to the actual database on disk or memory.
    • Is multithreaded
    • supports many simultaneous client connections
    • Supports multiple storage engines – both transactional or non-transactional
    • A single host can have multiple mysqld instances running.
  • Client programs
    • Utility to connect MySQL server.
    • programs are mysql, mysqladmin, mysqlcheck, mysqldump,mysqlimport, mysqlpump, mysqlsh, mysqlshow,mysqlslap
  • MySQL non-client programs.
    • Programs that act independently of the server.
    • myisamchk (table checks and repair operation) and myisampack (compressed read only version of MyISAM table)

Continue reading → MySQL – Architecture and Components

MySQL – Introduction

MySQL is a relational database management system or an RDBMS. It’s originally  developed by company founded in Sweden, MySQL AB.  It’s world’s most popular open source database.

MySQL Editions

Community Edition: Community Edition is the MySQL database for open source developers and technology enthusiasts who wan to get started with MySQL.  Its free of cost.

Enterprise Edition: Commercial customers have the flexibility of choosing from multiple editions to meet specific business and technical requirements.

  • MySQL Enterprise Edition
  • MySQL Standard Edition
  • MySQL Classic Edition
  • MySQL Cluster Carrier Grade Edition

Continue reading → MySQL – Introduction