When users complain that “the database is slow,” the culprit is not always an inefficient execution plan. Very often, it’s concurrency—sessions waiting on locks—silently throttling throughput. This post is a field-ready playbook based on the diagnostic queries you shared, refactored, explained, and sequenced into an end-to-end workflow. Use it to see blocking, measure impact, identify […]
Empowering the Optimizer with Precision at Every Change In the symphony of data, timing is everything. The modern enterprise pulses with an unceasing flow of transactions—millions of data changes racing through OLTP engines. Amid this dynamism, the Oracle optimizer stands as a maestro, orchestrating query performance. Yet, its brilliance is shadowed if it relies on […]
In earlier versions of Oracle Database, statistics were collected mainly through scheduled jobs using DBMS_STATS. This often resulted in stale statistics between collection intervals, especially in OLTP environments with frequent DML operations. Oracle 19c introduces Real-Time Statistics, a feature that collects optimizer statistics immediately during DML operations such as INSERT, UPDATE, MERGE, and CREATE TABLE […]
In Oracle Database 19c, the optimizer introduces a powerful feature called SQL Quarantine. This feature prevents recurring execution of problematic SQL statements that consume excessive resources or cause performance degradation. By automatically detecting high-resource SQL statements and placing them into quarantine, Oracle ensures that such queries cannot repeatedly impact system performance. This feature is especially […]