Databases@Powered by Passion

Month: June 2024

  • pg_amcheck: PostgreSQL corruption detection tool

    pg_amcheck: PostgreSQL corruption detection tool

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    by

    Osman DİNÇ
    ,

    PostgreSQL’s pg_amcheck is an essential tool for ensuring data integrity. Like Sherlock Holmes, it diligently detects anomalies, offering early detection of data corruption from hardware failures, software bugs, or system crashes. This tool, though not glamorous, is vital for proactive maintenance. Administrators can use pg_amcheck to identify issues.

  • Unusable and Parallel indexes on Flashback Data Archive Tables in 19.22

    Unusable and Parallel indexes on Flashback Data Archive Tables in 19.22

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    by

    Osman DİNÇ
    , ,

    After updating to release 19.22, issues arose with Flashback Data Archive (FDA). Despite bug fixes(35957640), internal indexes were created with the DEFAULT PARALLEL degree. Additionally, split operations caused related indexes to become unusable. A debug of the FBDA process revealed that the split operations lack an “UPDATE INDEXES” clause and no index rebuild operation is done internally. The test case provided highlights the issues. These concerns have been raised in a Service Request for resolution.

  • Transactional DDL in PostgreSQL

    Transactional DDL in PostgreSQL

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    by

    Osman DİNÇ
    ,

    PostgreSQL allows most DDL commands to be rolled back within a transaction block, unlike in many commercial database systems where DDL commands automatically commit the current transaction. With exceptions like DROP DATABASE and CREATE/DROP TABLESPACE, PostgreSQL ensures that all DDL operations are transactional, allowing for rollback as needed.

  • Holistic Patching for Oracle Enterprise Manager

    Holistic Patching for Oracle Enterprise Manager

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    by

    Osman DİNÇ
    ,

    This blog introduces the concept of holistic patching for Oracle Enterprise Manager, which simplifies and consolidates patch management for its various components. The method aims to reduce complexity and downtime by bundling updates into a single package, allowing organizations to focus on core activities. The process involves updating the OMSPatcher and executing a simple command for patching, significantly streamlining the patching process for Enterprise Manager.

  • Create a Function-based Index with NLSSORT

    Create a Function-based Index with NLSSORT

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    by

    Osman DİNÇ
    , ,

    The performance fluctuations in a query on production database were attributed to different NLS_SORT settings affecting SQL plan selection. The query showed varying performance with differing plan_hash_values despite a simple structure. Investigations revealed the impact of NLS settings on plan generation. Mimicking the behavior with setting NLS_SORT value in session confirmed the issue, leading to the creation of a functional index that resolved the problem, as evidenced by the subsequent execution plan.

  • Installing MariaDB and Configuring MaxScale NoSQL Protocol Module on Oracle Linux 8

    Installing MariaDB and Configuring MaxScale NoSQL Protocol Module on Oracle Linux 8

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    by

    Osman DİNÇ
    , ,

    The post details the installation and configuration of MariaDB and MaxScale with the NoSQL Protocol Module on Oracle Linux 8. The process involves downloading and installing MariaDB 11.4.2, configuring the MariaDB repositories for YUM, installing dependencies, setting up MaxScale as a database proxy, and establishing a NoSQL Listener. After verifying the services, the user prepares to interact with the NoSQL Protocol Module for MariaDB.