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What the new 11gR1 RDBMS changes benefit our application, you can read the article for a taste[@more@]Architecture:Hash Group By 10g: Hash Group By aggregation enabled instead of SORT GROUP BY _gby_hash_aggregation_enabledParallel query 10g: Parallel Query (PQ) has been enhanced to allow more queries to be parallelized New background:11g:DBRM (database resource manager) process is responsible for setting resource plans and other resource manager related tasks. DIA0 (diagnosab

Changes that affect SQL execution plans, such as upgrading a database or addingnew indexes, can severely impact SQL performance. As a result, DBAs spendenormous amount of time and effort identifying and fixing SQL statements thathave regressed due to the changes. SQL Performance Analyzer (SPA), a key featureof the Real Application Testing option introduced in Oracle Database 11g, canpredict and prevent SQL execution performance problems caused by systemchanges.[@more@]here is a simple step by st

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There are two ways to use dynamic sampling: The OPTIMIZER_DYNAMIC_SAMPLING parameter can be set at the database instance level and can also be overridden at the session level with the ALTER SESSION command. The DYNAMIC_SAMPLING query hint can be added to specific queries. eg:/*+ dynamic_sampling(t 0) */ level 0The Dynamic Sampling Levels[@more@]The sampling levels are as follows if the dynamic sampling level used is from a cursor hint or from the OPTIMIZER_DYNAMIC_SAMPLING initialization param

wbiadm@wbidevrk1p:[/home/wbiadm]# tnspingNL-00605: national language initialization failedNL-00605: national language initialization failedwbiadm@wbidevrk1p:[/home/wbiadm]# tnspingNL-00605: national language initialization failedNL-00605: national language initialization failedwbiadm@wbidevrk1p:[/home/wbiadm]# sqlplusError 5 initializing SQL*PlusNLS initialization error[@more@]nutshell for 2hrs searching the relative information, making a lot of change on binary, env, etc. Finally got the root c