Ways to avoid ORA-01555 snapshot too old error

Being the “Oracle DBA ” when the UNDO topic comes in an interview question. Normally interviewer as an about ORA-01555 snapshot too old error.   We reply about three or four lines as an answer For this question. For strong knowledge, we must have deep knowledge about this. Let’s have look on ORA-01555 snapshot too old error. ORA-01555: snapshot too old: rollback […]

Read More

Tuning the locks of SGA

This post describes some deep knowledge of SGA. LOCK_SGA is used to make sure that the contents from the SGA are not flushed, i.e data from the DB buffer cache not written back to disc. It is like to pin the contents of SGA. SGA_LOCK  locks the entire SGA into physical memory. It is usually advisable to […]

Read More


Today’s article is about to add some deep knowledge in the Oracle’s database knowledge. We are going to have look at basic elements of Oracle database. This article is most useful for freshers and beneficial for experienced DBAs too.   In Oracle Database we read about MEMORY_TARGET, SGA_TARGET, and PGA_AGGREGATE_TRAGET. Let’s have a technical definition of these teams. […]

Read More

How To Find DBID in NOMOUNT State

Oracle Database identifier in short DBID is an internal, unique identifier for an Oracle database. Database administrator must note down the DBID in safe place, so that any miss-happening to the database could be easily identified and recovered. In case it is required to recover SPFILE or control file from autobackup, such as disaster recovery, […]

Read More

Schema and Non-Schema Objects in Oracle Database

Oracle database contains schema objects like views, tables, triggers etc., and several other types of objects which are also stored in the database but are not contained in a schema. A schema is a collection of logical structures of data, or schema objects which is owned by a database user and has the same name […]

Read More

ORA-32004: obsolete or deprecated parameter(s) specified for RDBMS instance

I am getting ORA-32004 error while starting the database but all the parameters in spfile are fine. This issue came after upgrade the database from 10g to

How to fix the ORA-32004 error? Cause: ORA-32004 causes because one or more obsolete parameters were specified in the SPFILE. These depreciated parameters are still in use […]

Read More

VI editor shows the error Terminal too wide within Solaris

You may receive the following error when using VI editor within Solaris. I got this error when I was adding tns entry in tnsnames.ora file.

Here, VI will not allow to edit files. For editing you must increase the number of columns as shown below. To resolve this increase the number of columns using […]

Read More

Error in Process orapwd.exe and unable to find error file opw.msb

I was trying to install Oracle 11g R2(64bit) on Windows 7 64 bit OS. But While Creating Database using DBCA i got this error. Below is the screenshot. Error in Process: %ORACLE_HOME%\server\bin\orapwd.exe Unable to find error file %ORACLE_HOME%\RDBMS\opw<lang>.msb Resolution: Set proper Home and Path using cmd and launch the dbca.

Thank you for giving […]

Read More

KST tracing in Oracle

KST tracing is an in-memory tracing feature for Oracle RDBMS Database Server, this is similar to on-disk (KSD) tracing except it is stored in SGA. For on-disk tracing, we have many events like 10046 (sql_trace), 10053 (sql_optimizer), etc. Different to these on-disk tracing, KST tracing use a cyclic buffer in the SGA and we won’t […]

Read More