SAP BASIS,HANA AND ORACLE DBA BLOGS

Oracle Database 12c New Features - DBA Let us discuss new features of Oracle Database 12c Release 1.(12.1). Oracle says there are 500+ new features incorporated in 12c. We will see very few which are going to make a change in database world. Multitenant architecture: Pluggable databases (PDBs) and Container Database (CDB) is the new architecture for 12c.We can have may PDBs in a single database occurrence (CDB).PDBs are just like ordinary 11g or 10g databases. This architecture reducing the total cost of operations and improving the functionalists.It has other benefits like it is very easy to clone the database and new database creation.By doing one patching all PDBs will get upgraded. We can patch a PDB by unplug and plug in to different CDB. There is one set of background processes shared by the root and all PDBs.  There is a single redo log and a single control file for an entire CDB  There are single SGA shared by all pluggable databases. However, we can d...

IMPORTANT DATABASE TASKS   @Task 1: Evaluate the Database Server hardware >uname >uname -i  show the host name >uname -m >uname -a >lscpu   command which cpu in your machine >lsblk  command which show cpu >lsblk -a >fdisk -l >dmidecode -t processor @task 2 >database installation task 10.1.0.1.0 1 major database release number 2 database maintenance number 3 application server release number 4 component server release number 5 platform release number Checking Your Current Release Number SELECT * FROM PRODUCT_COMPONENT_VERSION; @Task 3: Plan the Database As the database administrator, you must plan: The logical storage structure of the database The overall database design A backup strategy for the database It is important to plan how the logical storage structure of the database will affect system performance and various database management operations. For example, before creating any tablespaces for your...

A BRIEF INTRO ON INDEX: Just like a book index helps us in finding the chapter and page number, an oracle index speeds up access time to the rows. Indexes are optional structures associated with tables. An index is also a schema object. We can drop an index without dropping the table it indexes. An index can be created explicitly or automatically. When we drop a table the corresponding indexes of the table are dropped. A unique index gets created when we create a unique key or primary key in a table definition.    The name of the index is the name of the constraint. Indexes can be unique or non-unique.  Unique indexes guarantee that no two rows of a table have duplicate values in the columns that define the index.  Non-unique indexes do not impose this restriction on the column values. The presences of more number of indexes on a table decreases the performance of DML statements, because Oracle must make changes to the indexes associated with the table For more c...

                        AWR REPORT ANALYSING                      BY ANAND GUPTA 1. Introduction 1.1. Purpose of Document AWR (Automatic Workload Repository) Reports are very handy during performance tuning of the database. These reports provide clear picture of database side activities. Various useful data is nicely documented in different sections in readable format. It becomes necessity to understand these reports for teams involved in activities like database tuning,performance/load testing or analyzing any performance issue. Purpose of the document is to enable the reader to understand basic AWR terminology and to use these details for understanding the database performance issues. 1.2. Scope This document describes how to utilize AWR reports to tune, ·       ...