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ORA-01578: ORACLE data block corrupted (file # XX, block # XXXXX) As this error (ORA-01578: ORACLE data block corrupted) message shows that you have a corrupt block. So for data corruption you need to check what is going wrong.Check alert logs for more detail. You can also use below sql:- select * from v$database_block_corruption; When i run the SQL. I found that one file # in my case 14 and some block 15353 is corrupted. As we know Corruption can occur in a table or index. So i have checked for this. In my case it was an index. So for a solution i just drop the index and created again and rebuild it. Just remember you cannot rebuild the index if it is having error ORA-01578: ORACLE data block corrupted. So drop and create index works for me and now i can rebuild. Dropping a index will not harm you much because it's already on corrupt block. Also i think when we create index again then it will take a different block. I am not sure about this because i have checked with sql after dr...

ORA-1254: TNS: could not resolve the connect identifier specified This error is because the connect identifier given, wrongalias, cannot be resolved into database connection details by the TNS (Transparent Network Substrate—not an acronym particularly worth remembering) layer of Oracle Net. The name resolution method to be used and its configuration is a matter for the database administrator. In this case, the error is obvious: the user entered the wrong connect identifier. The second connect attempt gives the correct identifier, orcl. This fails with ORA-12541: TNS:no listener This indicates that the connect identifier has resolved correctly into the address of a database listener, but that the listener is not actually running. Note that another possibility would be that the address resolution is faulty and is sending SQL*Plus to the wrong address. Following this error, the user should contact the database administrator and ask him or her to start the listener. Then try again. The thi...

Cómo solucionar ORA-12505, Listener no conoce actualmente de SID Este es un error muy común y realmente se chupar la sangre si no estás camino correcto. Intentaré explicarle sobre este error. Como se puede ver este error se muestra que el oyente está en marcha y en funcionamiento, pero no sirve el SID que está destinado a. Y sí primero usted necesita comprobar donde usted está haciendo frente a este error. Es en el lado del cliente o en el lado del servidor. Entonces, ¿cuál es el SID que está buscando este oyente? SID es el nombre de su base de datos o puede decir identificador de servicio, que es ayudar a identificar el servicio como utilizamos PROD para la producción de UAT para el servidor de pruebas. SID de la base de datos debe ser idéntico para evitar la confusión. Su longitud es de 8 caracteres sólo significa que no se puede extender más de 8 caracteres. ¿Cómo funciona el oyente? Como todos sabemos que es como un coche, que nos caen desde el aeropuerto al hotel, hahah lo siento,...

ORA-00240控製文件入隊持續超過XXX秒 說明：控製文件排隊持有超過字符串秒 原因：1.當前進程沒有在最大允許時間內釋放控製文件入隊。        2.未經發布的Bug 7570453 - [3 RAC NODE] ORA-00240在升級到10.2.0.4.0之後啟動的問題已被調查，該錯誤被關閉為Not Bug。開發人員確認這只是一個警告，讓DBA知道一個CF入隊被持有超過120秒。這不是一個錯誤，如果CF入隊超過900秒（15分鐘），則不會發生錯誤。 當數據庫中有很多數據文件時，會發生該消息。 DBWriter（dbw0）由於不得不打開這些數據文件而花費太多的時間來釋放CF入隊。 操作：1.重新發出失敗的任何命令，並與事件信息聯繫Oracle支持服務。    2.建議通過減少數據庫文件的數量來減少這個時間。更多的是建議使用較少但較大的數據文件，而不是較小的數據文件。   如何照顧Oracle審計   什麼是Oracle 10天規則？

How to solve ORA-12505, Listener does not currently know of SID   This is very common error and really it will suck your blood if you are not right path. I will try to explain you about this error. As you can see this error is showing itself that listener is up and running but not serving  the SID that it is meant for. And yes 1st you need to check where you are facing this error. Is it on client side or on server side. So what is the SID this listener looking for? SID is name for your database or you can say service identifier, That is help to to identify the the service like we use PROD for production UAT for testing server. SID of Database should be identical to avoid the confusion. It's length is 8 character only that means you can not extend it more then 8 character. Now how listener works ? As we all know its like a car, That drop us from airport to hotel, hahah sorry I am not good in examples. So let me explain technically, whenever you try to make connection from ...

“Error: ORA-02291: integrity constraint violated - parent key not found” Reason:    A Primary key does not have the same value as the foreign key. We will discuss it in detail later in this article. Action:   For  ORA-02291: integrity constraint violated - parent key not found  You may either delete the foreign key or the matching primary key can be added. In either way, you may try to get this error corrected. Let's understand more about ORA-02291: integrity constraint violated - parent key not found? The Oracle software brought us the strength by which multiple tables in the database can pass on information so efficiently. Not only this, there are numerous devices in this software which enables access to and sourcing data from multiple tables. You can easily execute complicated database issues without an unusual uncertainty by creating statements with the fantastic characteristic of this software. Realistically, if we talk about user or database no one is perf...

ORA-01033: ORACLE initialization or shutdown in progress Cause:  You are trying to access oracle database while  database is either starting up or shuting down (ORA-01033: ORACLE initialization or shutdown in progress). Action: For ORA-01033: ORACLE initialization or shutdown in progress you need to wait for some time. Then retry the operation again (connect after some time) to check if ORA-01033: ORACLE initialization or shutdown in progress is there or not. What is ORA-01033: ORACLE initialization or shutdown in progress? This is very common error and not occurs much. But you must have some idea if you face ORA-01033: ORACLE initialization or shutdown in progress occurs. As we know We can only set database to  Shutdown or startup using SYSDBA privileges. So you must have SYSDBA privileges to troubleshoot. I suggest  to  wait for 5mins because may be your DBA has shutdown the Database and it's in progress.Or if you are a DBA then check the status of databa...

Error: ORA-12714 ORA-12714  invalid national character set specified  ORA-12714 invalid national character set specified  is very common error and related to database parameters and sessions parameters. Cause  Only UTF8 and AL16UTF16 are allowed to be used as the national character set. Check your NLS_NCHAR_CHARACTERSET which is set using: select value from NLS_DATABASE_PARAMETERS where parameter = 'NLS_NCHAR_CHARACTERSET'; it should return UTF8 Or AL16UTF16 Action Ensure that the specified national character set is valid Please aware that at session level, some parameters could be different. If you want to be sure, compare the results of: select * from nls_database_parameters; with: select * from nls_session_parameters; Please find the below information:-     Bug No :- 2834295  Cause :-  declaring cursor for a function that returns a table of NVARCHAR2   Affects below products : Product ( Component ) Oracle Server (Rdbms) ...

1) Explain run time polymorphism in Java ? Polymorphism can be explained as an object's ability to adapt to the program's context and take multiple forms. The method overriding is an example of run time polymorphism. You can have a method in a subclass, which overrides the method in its super classes with the same name and signature. At run time, Java virtual machine determines the appropriate method to be called. 2) What are the rules (method access permission and exception) that needs to be followed, during method overloading and overriding ? During method Overloading, method name should remain same. But method signature can vary. Components of signature that can vary are Number of arguments Datatype of arguments Order of arguments During method Overriding, make sure that the method is not throwing checked exceptions that are new or higher than those declared by the overridden method.But we can't override Static and Final methods. 3) What is the difference between an Inte...