tns error

ORA-12154 : "TNS:could not resolve  service name"

Cause : oracle Net Services cannot locate the connect descriptor specified in the  tnsnames.ora configuration .

>> verify the tnsnames.ora files exists and that accessible .
>>verify that tnsnames.ora file in the location by the TNS_ADMIN environment variable.

ORA-12198: "TNS: could not find  path to destination  "
ORA-12203: "TNS: unable to connect the destination "

>> verify that you have correctly enter the service name of the database that you  want to connect.
>> verify that service name address ADDRESS parameter in the connect descriptor of your  tnsname.ora file are correct .
>> verify that you tnsname.ora  file stored in the directory defined in the TNS_ADMIN environment Variable

Looking forward for your suggestions.. please feel free to write to me.. Your help would definitely help to improve our blog. Chetan Yadav

Errors

GETTING THIS ERROR
ORA-01157:cannot identify/lock data file 1 - see DBWR trace file
ORA-01110:data file 1: 'D:\ORACLE\PRODUCT\10.2.0\ORADATA\HRMSD91\SYSTEM01.DBF'

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ERROR due to flash recovery area  and solution for it :



SQL> conn sys as sysdba
Enter password:
Connected to an idle instance.
SQL> startup
ORACLE instance started.

Total System Global Area  608174080 bytes
Fixed Size                  1292036 bytes
Variable Size             167774460 bytes
Database Buffers          436207616 bytes
Redo Buffers                2899968 bytes
Database mounted.
ORA-16038: log 3 sequence# 430 cannot be archived
ORA-19809: limit exceeded for recovery files
ORA-00312: online log 3 thread 1:
'D:\ORACLE\PRODUCT\10.2.0\ORADATA\HRM\REDO03.LOG'


SQL> alter system switch logfile
  2  ;
alter system switch logfile
*
ERROR at line 1:
ORA-01109: database not open


SQL> archive log list
Database log mode              Archive Mode
Automatic archival             Enabled
Archive destination            USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence     430
Next log sequence to archive   430
Current log sequence           432

SQL> show parameter db_recovery_file_dest

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
db_recovery_file_dest                string      D:\oracle\product\10.2.0\flash
                                                 _recovery_area
db_recovery_file_dest_size           big integer 3G
SQL> exit
Disconnected from Oracle Database 10g Enterprise Edition Release 10.2.0.3.0 - Pr
oduction
With the Partitioning, OLAP and Data Mining options

C:\Documents and Settings\Sundaresh>set oracle_sid=hrm

C:\Documents and Settings\Sundaresh>sqlplus

SQL*Plus: Release 10.2.0.3.0 - Production on Tue Sep 28 12:00:44 2010

Copyright (c) 1982, 2006, Oracle.  All Rights Reserved.

Enter user-name: sys as sysdba
Enter password:

Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.3.0 - Production
With the Partitioning, OLAP and Data Mining options

SQL> select name from v$database;

NAME
---------
HRM


SQL> alter system set db_recovery_file_dest_size=2G scope=both;

System altered.

SQL> ALTER DATABASE OPEN;
ALTER DATABASE OPEN
*
ERROR at line 1:
ORA-16014: log 3 sequence# 430 not archived, no available destinations
ORA-00312: online log 3 thread 1:
'D:\ORACLE\PRODUCT\10.2.0\ORADATA\HRM\REDO03.LOG'


SQL> alter system set db_recovery_file_dest_size=5g
  2  ;

System altered.

SQL> alter database open resetlogs;
alter database open resetlogs
*
ERROR at line 1:
ORA-01139: RESETLOGS option only valid after an incomplete database recovery


SQL> alter database open ;

Database altered.