Tagged: Oracle

Index Tuning

Oracle indexes can be tuned looking to three main characteristics: SELECTIVITY: you can calculate index selectivity using this formula: SELECT DISTINCT_KEYS/NUM_ROWS SELECTIVITY FROM DBA_INDEXES / Values range from 0 to 1, where 1 is the optimal value (UNIQUE indexes and PK), while with values near to 0 performance is lower CLUSTERING FACTOR: measures how many keys are stored in a single index block. This value is stored in DBA_INDEXES.CLUSTERING_FACTOR column. If it’s near to DBA_INDEXES_BLOCKS value then the index is good, if instead it’s near to DBA_INDEXES.NUM_ROWS performance is lower BLEVEL: Oracle indexes are stored in a B-TREE structure where...

Recover datafile corruption

   This Article show how to recover from a block failure. In this case partitioned table will be created and single block will be corrupted.   ·         Create Table   CREATE TABLE “TEST_TAB_2”    (   “ID” NUMBER(10,0) NOT NULL ENABLE,        “DESCRIPTION” VARCHAR2(50 BYTE) NOT NULL ENABLE,        “CREATED_DATE” DATE NOT NULL ENABLE    )   TABLESPACE “USERS”   PARTITION BY RANGE (“CREATED_DATE”)  (PARTITION “TEST_TAB_Q1”  VALUES LESS THAN (TO_DATE(‘ 2008-01-01 00:00:00’, ‘SYYYY-MM-DD HH24:MI:SS’, ‘NLS_CALENDAR=GREGORIAN’)) SEGMENT CREATION IMMEDIATE   TABLESPACE “USERS” ,  PARTITION “TEST_TAB_Q2”  VALUES LESS THAN (TO_DATE(‘ 2008-04-01 00:00:00’, ‘SYYYY-MM-DD HH24:MI:SS’, ‘NLS_CALENDAR=GREGORIAN’)) SEGMENT CREATION DEFERRED   TABLESPACE “USERS” ,  PARTITION...

Oracle Customer Experience Cloud

Oracle connects every interaction your customer has with your brand through the Oracle Customer Experience Cloud, making your customers’ experiences simple, consistent, and relevant throughout the customer lifecycle. Oracle Customer Experience Cloud helps you strengthen relationships with your customers with a platform that optimizes relevant engagements, improves service consistency, and ensures repeatable quality for each service engagement. Read more…… http://www.oracle.com/us/solutions/cloud/cloud-applications/cx/index.html