Courage is not the absence of fear, but rather the judgement that something else is more important than fear.
Type: Posts; User: krishnaindia2007; Keyword(s):
Courage is not the absence of fear, but rather the judgement that something else is more important than fear.
>>what is table mutation error and what is the occation it will happen
Follow the link
“Great dreams of great dreamers are always transcended.” - Abdul Khalam
SQL> SELECT greatest(12,54,2,75,142) from dual;
GREATEST(12,54,2,75,142)
------------------------
142
Max function takes only one parameter.
SQL> SELECT max(sal)...
Exports & Imports
1.In order to use exp & imp the catexp.sql must be run. It creates exp_full_database and impfull_database roles.
2.Objects owned by sys can't be exported.
3.To see help on...
Coming together is beginning
Keeping together is progress
Working together is success - Henry Ford
When an instance is started, if SPFILE is present, it will be used; otherwise, Oracle searches for a default PFILE.Oracle will scan the files in the following order:
1) spfileSID.ora
2)...
How can we know whether a parameter in parameter file is modifiable or not?
SQL> select distinct issys_modifiable from v$parameter;
ISSYS_MODIFIABLE
—————————
DEFERRED
FALSE
IMMEDIATE
How to know whether database is using pfile or spfile?
sql> select decode(value, null, 'pfile', 'spfile') "parameter file"
2 from sys.v_$parameter where name = 'spfile';
parame
------...
Advantages of SPFILE over PFILE
SPFILEs are available in Oracle 9i and above. All prior releases of Oracle are using PFILEs.
1.An SPFILE can be backed-up with RMAN and PFILE can't.
2.The...
SPFILE and PFILE
SPFILE stands for server parameter file.
Initialisation parameter file init.ora is also called as pfile.
These files hold setup parameters that defines attirbutes of instance....
“Any man who reads too much and uses his own brain too little falls into lazy habits of thinking” – - Albert Einstein
Why are you querying the database in this fashion with scripts that have not been tested ?
Indexes and between operator
Between operator will consider indexes if there index on a column.
Between is treated as a pair of comparison operators.
sql> select *
2 from emp
...
Indexes and Comparing columns in the same table
Comparing the columns in the same table makes an index useless.
sql> select empno, ename, job, mgr
2 from emp
3 where empno =...
Indexes and Like operator
you can take advantage of an index with like as long as you provide the first character in the pattern.
sql> select ename, job, sal
2 from emp
3 where...
Choosing Between Having and Where
Where puts condition on the table rows.
Having puts condition on grouped results.
The processing order is as follows.
1. Select rows with WHERE
2. Divide...
Control File Related Views
V$CONTROL FILE :- This view lists the names of the control files.
SQL> SELECT name
2 FROM v$controlfile;
NAME
Dynamic performanc views - IV
V$BGPROCESS :- This process describes the background processes.
V$BH:- This is a parallel server view. This view gives the status and number of pings for every...
Dynamic performanc views - III
V$instance :- It displays information of the current instance.
SQL> SELECT instance_name,
2 version,
3 status,
4...
Dynamic performanc views - II
II.v$sgastat
It constains detailed information on the system global area or contains information on sga segment sizes
sql> select *
2 from v$sgastat; ...
Dynamic performanc views - I
Dynamic performance views are identified by the prefix v_$.
Public synonyms for these views have the prefix v$.
The v$ views provide a continually updated look at...
Startup Command options
I.STARTUP FORCE
1.It aborts the current instance
2.Starts a new normal instance
II.STARTUP RESTRICT
1.It restrict connection to users with the RESTRICTED SESSION...
Starting Up a Database
Database can be started up in various stages.
I. Nomount
This stage is used to
1.Create a database
2.To recreate a control file.
It includes the following tasks
Database Shutdown -II
III.Shutdown Immediate
1.No New connections are allowed.
2.Connected clients are disconnected and Sql Statements in process are not completed.
3.Oracle rollback active...