PURPOSE This note explains the TOP-N Query, a new feature (as of 8.1.5) that allows users to query on ROWNUM and order results with ORDER BY. This functionality is similar to the offerings of other database software such as the “Top Values’ property option in Microsoft Access. Top-N Query to Solve ORDER BY…ROWNUM Inaccuracy: ==================================================…
1. When should you create more rollback segments? The number of rollback segments needed to prevent contention between processes can be determined with the help of the monitor rollback display and with the use of the v$waitstat table. The rollback monitor column “header waits/sec” gives an indication of the current rollback segment contention. Waits are…
dbms_logmnr.add_logfile(‘/export/home/oracle/paresh/arch1_558809894_83113.arc’, options => dbms_logmnr.new); dbms_logmnr.add_logfile(‘/export/home/oracle/paresh/arch1_558809894_83114.arc’, options => dbms_logmnr.addfile); dbms_logmnr.add_logfile(‘/export/home/oracle/paresh/arch1_558809894_83115.arc’, options => dbms_logmnr.addfile); dbms_logmnr.add_logfile(‘/export/home/oracle/paresh/arch1_558809894_83116.arc’, options => dbms_logmnr.addfile); execute DBMS_LOGMNR.START_LOGMNR(options => dbms_logmnr.dict_from_online_catalog); Then rename v$logmnr_contents to logminer_bak. Then run my_lbu.sql
Subject: How to Use DBMS_STATS to Move Statistics to a Different Database Doc ID: Note:117203.1 Type: FAQ Last Revision Date: 01-MAR-2007 Status: PUBLISHED To provide Oracle Support Services with statistics for debugging, please refer to the following article: Note 242489.1 Transferring Optimizer Statistics to Support Purpose: ======== The purpose of this article is to explain…
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Export with parameter file and import with same. =============================================== Task : I am exporting some tables from CS and importing thsoe tables into BASKET schema. /**************************************************** FILE NAME: exp_wo_data.par *******************/ userid=cs file=exp_bskt_15MAR07.dmp compress=N grants=N log=bskt_exp_15MAR07.log ROWS=N triggers=N statistics=NONE tables=(BSKT_AGENT_BASKET_CALL_DETAIL , BSKT_AGENT_ORDER_NOTE , BSKT_BASKET_ITEM_TYPE , BSKT_DISCOUNT_APPLY_TYPE , BSKT_DISCOUNT_REASON , BSKT_ITEM_CALC_PRICING , BSKT_ITEM_PRICING_XREF , BSKT_ITEM_SUB_PRODUCT , BSKT_PAYMENT_DETAIL…
http://www.mail-archive.com/oracle-l@fatcity.com/msg79721.html Oh yeah, I forgot to say that in 9.2.0.3 the shared pool was broken up into “heaps” (Oracle terminology) but whatever fancy stuff they were trying to accomplish by doing this (I think part of the magical self-tuning initiative) was buggy and this hastened the fatal 4031 situation. There is a parameter (so I…
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Note:396940.1 How many Subpools will I have by default? The number of subpools is calculated using a simple algorithm. First, a subpool must be at least 128MB in 9i releases and at least 256MB in 10g releases. Bugs and internal tests show that subpools around 500M will work most efficiently and in future versions, we…
Here is the syntax: analyze index CUSTOMER_LASTNAME_IND validate structure; It populates the SYS.INDEX_STATS view only. The SYS.INDEX_STATS view can be accessed with the public synonym INDEX_STATS. The INDEX_STATS view will hold information for one index at a time: it will never contain more than one row. Therefore you need to query this view before you…
exp userid=cs file=gift_cert_07FEB07.dmp log=gift_cert_07FEB07.log compress=N grants=N tables=gift_certificate statistics=none query=”where dt_crtd >= to_date(’02-04-2007 10:00:00′,’MM-DD-YYYY HH24:MI:SS’)” /* WITH LOG */ imp userid=cs file=gift_cert_07FEB07.dmp log=gift_cert_07FEB07_imp.log ignore=Y grants=N fromuser=cs touser=cs statistics=none constraints=N buffer=10485760 commit=y indexes=N feedback=5000
When you create a composite B-tree index, you should consider the following. The most restrctive condition: The condition that returns the least number of rows. The column that is involved in this condition, should be the leading column of B-tree index. So for finding the candidate of composite index columns, column order should be.. (…
