Connection Descriptor Error
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connect to the appropriate Oracle database, we'll need to expound a bit on how Oracle behaves and, therefore, what is causing this issue in the first place. SIDs vs SERVICE_NAMES It ora 12505 error in sql developer is important to understand the (slight) difference between what Oracle defines as a listener refused the connection with the following error ora-12505 in oracle sql developer SID compared to a SERVICE_NAME, as we'll use this information to create a proper connection string later on. In ora-12505 tns listener does not currently know of sid Oracle, the system identifier (or SID) is a local identifier of up to eight characters in length that is used to identify a particular database and differentiate it from other databases on the ora 12505 error in oracle 11g system. Often the SID is the prefix word or DB_UNIQUE_NAME that precedes the DB_DOMAIN. For example, the SID of our bookstore database, as seen in in the full global database name of bookstore.company.com. SERVICE_NAMES, on the other hand, represent the names by which database instances can be connected to. A SERVICE_NAME will typically follow the format of the SID followed by the database domain, like
Listener Refused The Connection With The Following Error Ora-12514
so: DB_UNIQUE_NAME.DB_DOMAIN The TNS Listener When a client is attempting to connect to an Oracle database, rather than connecting to the database directly, there is a broker service that intervenes and handles the connection request for the client. This broker application is known as the listener and it performs the task of listening for incoming client requests. When a request is received, the listener processes and forwards that request onto the appropriate Oracle database server using a service handler, which just acts as the connection between the listener and the database server. TNS Names and Configuration When connecting to an Oracle database, typically your database server will have tnsnames.ora, which is a configuration file that informs the server about NET_SERVICE_NAMES which are valid database connections. By default, this file is located at ORACLE_HOME/network/admin. For example, a NET_SERVICE_NAME descriptor in tnsnames.ora may be formatted like this: myDatabaseNetService = (DESCRIPTION = (ADDRESS = (PROTOCOL = tcp)(HOST = localhost)(PORT = 1521)(QUEUESIZE = 100)) (CONNECT_DATA = (SERVICE_NAME = bookstore.company.com) ) ) This would define a NET_SERVICE_NAME using the SERVICE_NAME we discussed earlier (bookstore.company.com) and connecting to localhost through port 1521. Connection String With a bit more kn
Services Connecting to a Database Service Understanding Service Handlers Understanding Naming Methods Enhancing Service Accessibility using Multiple Listeners Understanding Database Instances A database has at least one instance.
Listener Does Not Currently Know Of Service Requested In Connect Descriptor
An instance is comprised of a memory area called the System Global ora-12514 error in oracle 11g Area (SGA) and Oracle background processes. The memory and processes of an instance efficiently manage the associated database's ora-12514 tns could not resolve the connect identifier specified data and serve the database users. Note: An instance also manages other services, such as Oracle XML DB. Figure 2-1 shows two database instances, sales and finance, associated with their https://chartio.com/resources/tutorials/how-to-fix-ora-12505-tns-listener-does-not-currently-know-of-sid-given-in-connect-descriptor respective databases and service names. Figure 2-1 One Instance for Each Database Description of "Figure 2-1 One Instance for Each Database" Instances are identified by an instance name, sales and finance in this example. The instance name is specified by the INSTANCE_NAME initialization parameter. The instance name defaults to the Oracle system identifier (SID) of the database instance. Some hardware architectures https://docs.oracle.com/cd/E11882_01/network.112/e41945/concepts.htm allow multiple computers to share access to data, software, or peripheral devices. Oracle Real Application Clusters (Oracle RAC) (Oracle RAC) can take advantage of such architecture by running multiple instances on different computers that share a single physical database. Figure 2-2 shows an Oracle RAC configuration. In this example, two instances, sales1 and sales2, are associated with one database service, sales.us.example.com. Figure 2-2 Multiple Instances Associated with an Oracle RAC Database Description of "Figure 2-2 Multiple Instances Associated with an Oracle RAC Database" Understanding Database Services An Oracle database is represented to clients as a service. A database can have one or more services associated with it. Figure 2-3 shows two databases, each with its own database service for clients. One service, sales.us.example.com, enables salespersons to access the sales database. Another service, finance.us.example.com, enables financial analysts to access the finance database. Figure 2-3 One Service for Each Database Description of "Figure 2-3 One Service for Each Database" The sales and finance databases are each identified by a service name, sales.us.example.com and finance.us.example.com, respectively. A service name is a logical representat
here for a quick overview of the site Help Center Detailed answers http://stackoverflow.com/questions/18192521/ora-12505-tnslistener-does-not-currently-know-of-sid-given-in-connect-descript to any questions you might have Meta Discuss the workings and policies of this site About Us Learn more about Stack Overflow the company Business Learn more about hiring developers or posting ads with us Stack Overflow Questions Jobs Documentation Tags Users Badges Ask Question x Dismiss Join the Stack error in Overflow Community Stack Overflow is a community of 4.7 million programmers, just like you, helping each other. Join them; it only takes a minute: Sign up ORA-12505, TNS:listener does not currently know of SID given in connect descriptor up vote 81 down vote favorite 21 I have installed Oracle 11g ora 12505 error Express Edition Release 2 in my windows 7 64 bit OS and tried to execute JDBC program, then I got the following error: java.sql.SQLException: Listener refused the connection with the following error: ORA-12505, TNS:listener does not currently know of SID given in connect descriptor at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:412) at oracle.jdbc.driver.PhysicalConnection.