Oracle database TNS Common Error Resolution

1, Ora-12541:tns: No listener

Cause: The listener is not started or the listener is corrupted. If the former, use the command net start Oracleorahome10gtnslistener (the name may differ), and if it is the latter, use the "Net Configuration Assistant" Tool Wizard, "Listener Configuration" Add a listener (basically do not write any information, all the way OK.) You may need to delete all the listeners before adding them!)

　2, Ora-12500:tns: The listener could not start the dedicated server process or ORA-12560:TNS: Protocol adapter Error

Reason: Oracle's database service is not started. Use the command net start oracleserviceoradb (ORADB is the database name). If it is still unresolved, continue looking down.

　3. If the database service fails to start, it is most likely that its registry key value is corrupted and the best practice is the following two steps:

1) Oradim-delete-sid oradb Delete database service items

2) Oradim-new-sid oradb New database service items

Note: If there is an error in this process, restart the computer!

　4, Ora-12154:tns: can resolve service name

Reason: Oracle's Network service name is not configured correctly. Use the "Local Network Service name configuration" Net8 Configuration Assistant Tool Wizard to configure TNS. If it is still unresolved, continue looking down.

　5, Ora-1034:tns:oracle is not available

Cause: Oracle's database service started correctly, but the database did not open!

To use the command:

1) SVRMGRL start Service Manager

2 Connect internal to internal identity landing

3) startup Open the database

　　6, Ora-12560:tns: Protocol adapter error (stubborn)

Reason: Unknown.

Solution: Must kill skill--opens "The Windows Task Manager", kills the ORACLE.exe and the ORADIM.exe process, writes own Ora_startup.bat, executes!

PS:

　　1, Ora_startup.bat:

net start Oracleorahome81tnslistener

net start oracleserviceoradb

SVRMGRL generally not, but sometimes it is not, the concrete steps see step 5th.

　2, Ora_shutdown.bat:

net stop Oracleorahome81tnslistener

net stop oracleserviceoradb

　　3, Oracle related service name see the service name that begins with Oracle in the services of administrative Tools

　　1, TNS-12154 Error or ORA-12154

Feature: Sql*net did not find a connection string or alias

　Reason 1:(1) The Tnsnames.ora file was not found, and the default path for the file is:

Windows 95/98 Client Sql*net 2.x-orawin95networkadmin Net8-orawin95net80admin Net8i-oracleora81networkadmin Windows NT Client Sql*net 2.x-orantnetworkadmin Net8-orantnet80admin Net8i-oracleora81networkadmin UNIX Client $ORACLE _home/network/admin Or/etc Or/var/opt/oracle

. Setting Tns_admin on the client

Set tns_admin in registry hkey_local_machinesoftwareoracle. Tns_admin point to Tnsnames.ora file location

Measures: Check file location as described above

　　Reason 2:(2) TNSNAMES. The content in the Ora file is not well-formed

Measures: Check the file format, the standard format is as follows:

DEV1. World = (DESCRIPTION = (Address_list = (address = (PROTOCOL = tcp) (Host = 145.45.78.56) (Port = 1521)) (Connect_data = (SID = ORCL))

　　Reason 3: (3) TNSNAMES. Ora is inconsistent with Sqlnet.ora

Measures: Sqlnet. The ORA format is as follows:

Trace_level_client = Off Sqlnet. Authentication_services = (NONE) NAMES. Directory_path = (TNSNAMES) AUTOMATIC_IPC = Off

Because there is no names.default_domain=world, the Dev1.world connection string cannot be connected and can be increased in Tnsnames.ora

DEV1 = (DESCRIPTION = (Address_list = (address = (PROTOCOL = TCP) (Host = 145.45.78.56) (Port = 1521)) (Connect_data = (SID = ORCL))

You can connect at this time.

2, NL-00462 Error or ORA-00462

Feature: The listener cannot start

Reason: LISTENER. Ora file content errors, such as parentheses mismatch, parameter name errors, extra spaces, and so on.

Action: Re-edit a file

3, NL-00405 Error or ORA-00405

Features: LISTENER. The Ora file is unreadable or cannot be found

Reason: LISTENER. Ora file content errors, such as parentheses mismatch, parameter name errors, extra spaces, and so on.

Action: Make sure the file location is $oracle_home/network/admin under the default directory, or set the environment variable Tns_admin point to the location of the file.

　4, TNS-01155 Error or ORA-01155

Features: LISTENER. Sid_list_listener variable Assignment in ora file is not correct

Reason: LISTENER. Ora file content error, Sid_list_listener variable assignment is not correct.

Measures: To ensure the correct value in the file, $ORACLE _home/network/admin/samples directory has a sample file for reference.

　5, TNS-12537, TNS-12560, TNS-00507 Error

Features: LISTENER. An invalid protocol adapter was referenced in the Ora file

Reason: LISTENER. Procotol variable Assignment in ora file is not correct.

Measures: To ensure the correct value in the file, the general use of TCP protocol, $ORACLE _home/network/admin/samples directory has a sample file, available for reference. Check protocol with adapters Tnslsnr

　　6, TNS-12203 Error

Feature: Cannot connect to target

Cause: Whether the listener is started or if the alias is configured

Action: Check whether the listener is started, such as Lsnrctl status; Check tnsnames.ora alias configuration

　7, TNS-12533 Error

Feature: Cannot connect to target

Reason: illegal address parameter,

Measures: Check the address parameters of the Tnsnames.ora

1 use tnsping net_service_name to test whether the network service name is configured correctly!

2) test the network service name with the Sqlplus program, such as Sqlplus system/manager@test. If you cannot connect to the database, the test Network service name (NET services) in the Tnsname.ora file is followed by the value of the Sqlnet.ora file Names.default_domain parameter,