Category: Oracle
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v$sql INVALIDATION column and Prevent SQL Cursor Invalidation
This content highlights the impact of SQL cursor invalidation on system performance and suggests solutions to reduce the number of hard parses. It emphasizes the importance of avoiding hard parses in OLTP systems and discusses reasons for SQL cursor invalidation, such as schema changes, statistics updates and parameter changes. The implementation of atomic refresh for materialized views is presented as a solution to reduce SQL cursor invalidations leading to improved performance in OLTP systems.
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Oracle Database 23ai Fuzzy Matching and Similarity Searches
This content provides a tutorial on performing similarity searches in Oracle 11g+ databases using various algorithms like Jaro-Winkler and Levenshtein by using ULT_MATCH package. It also introduces the FUZZY_MATCH package in Oracle 23ai release, allowing for greater flexibility and alignment with developer needs. The post includes sample SQL queries for implementing these algorithms and a referral to the Oracle 23ai SQL Language Reference for more information.
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Unified Audit Trail: SQL Text Not Recorded in Syslog
The Oracle Database 12.2 or later uses Unified Auditing to track activity. However, certain fields are not captured in the syslog of Unified Audit Trail, impacting the completeness of log data. To address this, a simple method of sharing audit records with SIEM tools like WAZUH involves using SQL/JSON functions to stream data in NDJSON format. This can be done using a shell script scheduled with cron.
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Comparing Oracle Users’ Decrypted Passwords with RockYou2024
The “RockYou2024” password leak contains 9,948,575,739 unique plaintext passwords, making it valuable for cybercriminals aiming to perform brute-force attacks. Ensuring the security of Oracle databases is crucial, as weak passwords pose a significant vulnerability. To mitigate this risk, it is recommended to compare database passwords against the 1 million most common ones. A provided SQL script guides this process and demonstrates how to perform the comparison.
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Unusable and Parallel indexes on Flashback Data Archive Tables in 19.22
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.
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Holistic Patching for Oracle Enterprise Manager
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.
Osman’s DBlog 