Change the display name for the connection node: choose Properties from the node's popup menu and click the ellipsis button for the Display Name property. Although the steps above demonstrate the case of connecting to a local database instance, the steps for connecting to a remote database are the same.
The only difference is that instead of specifying localhost as the hostname, enter the IP address or hostname of the remote machine where Oracle Database is installed. A common way of interacting with databases is running SQL commands in an SQL editor or by using database management interfaces. For example, Oracle Database XE has a browser-based interface through which you can administer the database, manage database objects, and manipulate data. Although you can perform most of the database-related tasks through the Oracle Database management interface, in this tutorial we demonstrate how you can make use of the SQL Editor in the NetBeans IDE to perform some of these tasks.
The following exercises demonstrate how to create a new user, quickly recreate a table, and copy the table data. Let's create a new database user account to manipulate tables and data in the database. To create a new user, you must be logged in under a database administrator account, in our case, the default system account created during database installation. This command creates a new user jim with the password mypassword. The default tablespace is users and the allocated space is unlimited.
In real life, a database administrator creates custom roles and fine tunes privileges for each role. For more information about roles and privileges, see Oracle Database Security Guide. A tablespace is a logical database storage unit of any Oracle database.
In fact, all of the database's data is stored in tablespaces. You create tables within allocated tablespaces. If a default tablespace is not explicitly assigned to a user, the system tablespace is used by default it is better to avoid this situation.
In this exercise you will recreate a table by using the structure of another table. In this example, you want the user jim to create a copy of the Departments table in his schema by recreating the table from the hr database. Before you create the table you will need to disconnect from the server and log in as user jim.
When you created the user jim , the Select privilege was limited to the Departments table. If you want to copy the data from the original Departments table to the new table, you can enter the data manually in the table editor or run an SQL script on the new table to populate the table. The following script will populate the first row of the new table with the data from the original table.
You can retrieve the SQL script for populating the table from the original table by performing the following steps. By running SQL queries, you can add, modify and delete data maintained in database structures. At first, create the second table named Locations in the jim schema stay logged under the jim's user account.
If more than one database connection is registered with the IDE, the IDE might prompt you to select the correct connection. Note that you cannot insert new records directly in the results of this query, as you could do in the representation of a single table.
For this, the database user should be granted the privilege to Create View that our sample user does not have. You can log in under the system account, grant jim the Create View privilege with this SQL statement: 'grant create view to jim;' and try creating your own view. Important: If there is no such line in php. For example, some applications warn users not to hit the submit button twice.
When a warning is ignored, users may unintentionally purchase items twice or submit multiple payments for the same invoice. Application Continuity also referred to as Replay is a general purpose, application-independent infrastructure for Active GridLink and Generic data sources that enables the recovery of work from an application perspective and masks many system, communication, and hardware failures.
The semantics assure that end-user transactions can be executed on time and at-most-once. The only time an end user should see an interruption in service is when the outage is such that there is no point in continuing.
Following any outage that is due to a loss of database service, planned or unplanned, Application Continuity rebuilds the database session. If a callback is registered, issues a callback allowing the application to re-establish initial state for that session. The Oracle driver determines the timing of replay calls. Calls may be processed chronologically or using a lazy processing implementation depending on how the application changes the database state.
The replay is controlled by the Oracle 12c Database Server. For a replay to be approved, each replayed call must return exactly the same client visible state that was seen and potentially used by the application during the original call execution. The following section provides requirements and items to consider when using Application Continuity with WebLogic applications:.
For this release, Application Continuity only supports read and write transactions. XA transactions are not supported.
See Selecting the Driver for Application Continuity. Deprecated oracle. Occurrences should be changed to use either the corresponding oracle. Oracle recommends using the standard java. Application Continuity works by storing intermediate results in memory. An application may run slower and require significantly more memory than running without the feature.
Using the WebLogic statement cache is not supported. The size of the WebLogic statement cache must be set to 0. There are additional limitations and exceptions to the Application Continuity feature which may affect whether your application can use Replay. For example:. The following sections provide information on how to implement Application Continuity in your environment:.
The administration console does not have an entry for a replay driver. To configure the JDBC replay data source, you must manually replace the existing Oracle data source class with the replay data source class oracle.
Make sure the Database Type is Oracle. See Requirements and Considerations. To create a connection initialization callback, your application must implement the initialize java. Connection connection method of the oracle. ConnectionInitializationCallback interface. Only one callback can be created per connection pool.
The callback is ignored if a labeling callback is registered for the connection pool. Otherwise, the callback is executed at every connection check out from the pool and at each successful reconnect following a recoverable error at replay. Use of the same callback at run time and at replay ensures that exactly the same initialization that was used when the original session was established is used during the replay. If the callback invocation fails, replay is disabled on that connection.
Only one callback may be registered on a connection pool. The following example demonstrates registering an initialization callback that is implemented in the MyConnectionInitializationCallback class:. The callback can also be registered by entering the callback class in the Connection Initialization Callback attribute on the Oracle tab for a data source in the Administration Console.
The following example demonstrates removing an initialization callback:. Use -Djava. Global Data Services GDS enables you to use a global service to provide seamless central management in a distributed database environment. A global server provides automated load balancing, fault tolerance and resource utilization across multiple RAC and single-instance Oracle databases interconnected by replication technologies such as Data Guard or GoldenGate.
The following section provides requirements and considerations when using Global Database Services in WebLogic Server:. For update operations to be handled correctly, you must define a service for updates that is only enabled on the primary database. Define a separate service for Read-only operations that is located on the primary and secondary databases. Since only a single service can be defined for a URL and a single URL for a datasource configuration, one datasource must be defined for the update service and another datasource defined for the read-only service.
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