Life cycle of Database Migration from Oracle, DB2 to PostgreSQL

Many businesses which use Database management systems like Oracle, DB2 & MS SQL are unreliable these days. Moreover, the costs incurred in maintaining these systems and its product licenses keeps on increasing. As the competitors are migrating over to the new technologies and tools available in the market, it is necessary for these businesses to migrate to new environment which is efficient, consistent and reliable to stay in the market and the technologies used in the current environment have become obsolete or no longer serve the business purpose. PostgreSQL has emerged as a top open-source RDBMS software. Since there is no licensing cost associated with it most of the companies are planning to migrate the databases which are currently running on other RDBMS like Oracle, DB2, MS SQL server to PostgreSQL. This report summarizes the various methodologies, procedures and techniques involved in successfully migrating the data from Oracle to PostgreSQL & DB2 to PostgreSQL. Migration is not a simple effort there should be proper planning and testing involved in this right from database connectivity to performance analysis. In this paper we are going to cover most of the steps which we need to consider before the migration and after the migration like choosing the correct tools for implementing the migration, time taken to migrate ,data compatibility, code conversion, application connectivity to database, database configuration parameters, performance analysis, replication setups, database monitoring, patching and backup strategies.

Architecting petabyte-scale analytics by scaling out Postgres on Azure with Citus

The story about powering a 1.5 petabyte analytics application with 2816 cores and 18.7 TB of memory in the Citus cluster at the Microsoft. The Windows team measures the quality of new software builds by scrutinizing 20,000 diagnostic metrics based on data flowing in from 800 million Windows devices. At the same time, the team evaluates feedback from Microsoft engineers who are using pre-release versions of Windows updates. At Microsoft, the Windows diagnostic metrics are displayed on a real-time analytics dashboard called “Release Quality View” (RQV), which helps the internal “ship-room” team assess the quality of the customer experience before each new Windows update is released. Given the importance of Windows for Microsoft’s customers, the RQV analytics dashboard is a critical tool for Windows engineers, program managers, and execs.

Миграция данных из Oracle в PostgreSQL с использованием инструмента Pentaho

При миграции данных из одной СУБД в другую встает вопрос: выбрать сторонний инструмент или написать миграцию самому? Компании, пытаясь вырасти компетенции внутри себя, выбирают второй вариант. И наталкиваются на изобретение собственных "велосипедов". Однако на рынке есть мощные бесплатные инструменты миграции данных. Одним из таких инструментов является Pentaho Data Integration, входящий в пакет Pentaho Community Edition. В докладе будет рассмотрено применение данного пакета для миграции данных между СУБД Oracle и PostgreSQL. Особое внимание будет уделено проблемам, возникающим при использовании данного инструмента, и задачам тестирования на полноту и целостность мигрируемых данных.

Небольшая видео-иллюстрация:

Unlocking the Postgres Lock Manager

Locking is critical for providing high concurrency for any database — you cannot fully utilize your hardware if locking is throttling its use. This talk explores all aspects of locking in Postgres by showing queries and their locks; covered lock types include row, table, shared, exclusive, and advisory lock types. The high concurrency provided by Multiversion Concurrency Control (MVCC) is also covered.

Slides are at https://momjian.us/main/writings/pgsql/locking.pdf