Connection __LINK_

A Connection object's database is able to provide information describing its tables, its supported SQL grammar, its stored procedures, the capabilities of this connection, and so on. This information is obtained with the getMetaData method.

Note: When configuring a Connection, JDBC applications should use the appropriate Connection method such as setAutoCommit or setTransactionIsolation. Applications should not invoke SQL commands directly to change the connection's configuration when there is a JDBC method available. By default a Connection object is in auto-commit mode, which means that it automatically commits changes after executing each statement. If auto-commit mode has been disabled, the method commit must be called explicitly in order to commit changes; otherwise, database changes will not be saved.

Connection

DOWNLOAD 🔥 https://urluso.com/2y5I6R 🔥

A new Connection object created using the JDBC 2.1 core API has an initially empty type map associated with it. A user may enter a custom mapping for a UDT in this type map. When a UDT is retrieved from a data source with the method ResultSet.getObject, the getObject method will check the connection's type map to see if there is an entry for that UDT. If so, the getObject method will map the UDT to the class indicated. If there is no entry, the UDT will be mapped using the standard mapping.

A user may create a new type map, which is a java.util.Map object, make an entry in it, and pass it to the java.sql methods that can perform custom mapping. In this case, the method will use the given type map instead of the one associated with the connection.

For example, the following code fragment specifies that the SQL type ATHLETES will be mapped to the class Athletes in the Java programming language. The code fragment retrieves the type map for the Connection object con, inserts the entry into it, and then sets the type map with the new entry as the connection's type map. java.util.Map map = con.getTypeMap(); map.put("mySchemaName.ATHLETES", Class.forName("Athletes")); con.setTypeMap(map);

This method generally cannot be called to determine whether a connection to a database is valid or invalid. A typical client can determine that a connection is invalid by catching any exceptions that might be thrown when an operation is attempted.

The driver stores the value specified in a suitable location in the database. For example in a special register, session parameter, or system table column. For efficiency the driver may defer setting the value in the database until the next time a statement is executed or prepared. Other than storing the client information in the appropriate place in the database, these methods shall not alter the behavior of the connection in anyway. The values supplied to these methods are used for accounting, diagnostics and debugging purposes only.

If the value specified to this method is greater than the maximum length for the property the driver may either truncate the value and generate a warning or generate a SQLClientInfoException. If the driver generates a SQLClientInfoException, the value specified was not set on the connection.

The following are standard client info properties. Drivers are not required to support these properties however if the driver supports a client info property that can be described by one of the standard properties, the standard property name should be used. ApplicationName - The name of the application currently utilizing the connection ClientUser - The name of the user that the application using the connection is performing work for. This may not be the same as the user name that was used in establishing the connection. ClientHostname - The hostname of the computer the application using the connection is running on.

It is possible that the aborting and releasing of the resources that are held by the connection can take an extended period of time. When the abort method returns, the connection will have been marked as closed and the Executor that was passed as a parameter to abort may still be executing tasks to release resources.

Note: This method is intended to address a rare but serious condition where network partitions can cause threads issuing JDBC calls to hang uninterruptedly in socket reads, until the OS TCP-TIMEOUT (typically 10 minutes). This method is related to the abort() method which provides an administrator thread a means to free any such threads in cases where the JDBC connection is accessible to the administrator thread. The setNetworkTimeout method will cover cases where there is no administrator thread, or it has no access to the connection. This method is severe in it's effects, and should be given a high enough value so it is never triggered before any more normal timeouts, such as transaction timeouts.

The Statement.setQueryTimeout() timeout value is independent of the timeout value specified in setNetworkTimeout. If the query timeout expires before the network timeout then the statement execution will be canceled. If the network is still active the result will be that both the statement and connection are still usable. However if the network timeout expires before the query timeout or if the statement timeout fails due to network problems, the connection will be marked as closed, any resources held by the connection will be released and both the connection and statement will be unusable.

The pooling manager does not need to call beginRequest if: The connection pool caches PooledConnection objects Returns a logical connection handle when getConnection is called by the application The logical Connection is closed by calling Connection.close prior to returning the PooledConnection to the cache.

The pooling manager does not need to call endRequest if: The connection pool caches PooledConnection objects Returns a logical connection handle when getConnection is called by the application The logical Connection is closed by calling Connection.close prior to returning the PooledConnection to the cache.

A connection (session) with a specific database. SQL statements are executed and results are returned within the context of a connection. A Connection object's database is able to provide information describing its tables, its supported SQL grammar, its stored procedures, the capabilities of this connection, and so on. This information is obtained with the getMetaData method. Note: When configuring a Connection, JDBC applications should use the appropriate Connection method such as setAutoCommit or setTransactionIsolation. Applications should not invoke SQL commands directly to change the connection's configuration when there is a JDBC method available. By default a Connection object is in auto-commit mode, which means that it automatically commits changes after executing each statement. If auto-commit mode has been disabled, the method commit must be called explicitly in order to commit changes; otherwise, database changes will not be saved. A new Connection object created using the JDBC 2.1 core API has an initially empty type map associated with it. A user may enter a custom mapping for a UDT in this type map. When a UDT is retrieved from a data source with the method ResultSet.getObject, the getObject method will check the connection's type map to see if there is an entry for that UDT. If so, the getObject method will map the UDT to the class indicated. If there is no entry, the UDT will be mapped using the standard mapping. A user may create a new type map, which is a java.util.Map object, make an entry in it, and pass it to the java.sql methods that can perform custom mapping. In this case, the method will use the given type map instead of the one associated with the connection. For example, the following code fragment specifies that the SQL type ATHLETES will be mapped to the class Athletes in the Java programming language. The code fragment retrieves the type map for the Connection object con, inserts the entry into it, and then sets the type map with the new entry as the connection's type map. java.util.Map map = con.getTypeMap(); map.put("mySchemaName.ATHLETES", Class.forName("Athletes")); con.setTypeMap(map); See Also:DriverManager.getConnection(java.lang.String, java.util.Properties), Statement, ResultSet, DatabaseMetaDataField SummaryFields Modifier and TypeField and Descriptionstatic intTRANSACTION_NONEA constant indicating that transactions are not supported.static intTRANSACTION_READ_COMMITTEDA constant indicating that dirty reads are prevented; non-repeatable reads and phantom reads can occur.static intTRANSACTION_READ_UNCOMMITTEDA constant indicating that dirty reads, non-repeatable reads and phantom reads can occur.static intTRANSACTION_REPEATABLE_READA constant indicating that dirty reads and non-repeatable reads are prevented; phantom reads can occur.static intTRANSACTION_SERIALIZABLEA constant indicating that dirty reads, non-repeatable reads and phantom reads are prevented.Method SummaryAll Methods Instance Methods Abstract Methods Modifier and TypeMethod and Descriptionvoidabort(Executor executor)Terminates an open connection.voidclearWarnings()Clears all warnings reported for this Connection object.voidclose()Releases this Connection object's database and JDBC resources immediately instead of waiting for them to be automatically released.voidcommit()Makes all changes made since the previous commit/rollback permanent and releases any database locks currently held by this Connection object.ArraycreateArrayOf(String typeName, Object[] elements)Factory method for creating Array objects.BlobcreateBlob()Constructs an object that implements the Blob interface.ClobcreateClob()Constructs an object that implements the Clob interface.NClobcreateNClob()Constructs an object that implements the NClob interface.SQLXMLcreateSQLXML()Constructs an object that implements the SQLXML interface.StatementcreateStatement()Creates a Statement object for sending SQL statements to the database.StatementcreateStatement(int resultSetType, int resultSetConcurrency)Creates a Statement object that will generate ResultSet objects with the given type and concurrency.StatementcreateStatement(int resultSetType, int resultSetConcurrency, int resultSetHoldability)Creates a Statement object that will generate ResultSet objects with the given type, concurrency, and holdability.StructcreateStruct(String typeName, Object[] attributes)Factory method for creating Struct objects.booleangetAutoCommit()Retrieves the current auto-commit mode for this Connection object.StringgetCatalog()Retrieves this Connection object's current catalog name.PropertiesgetClientInfo()Returns a list containing the name and current value of each client info property supported by the driver.StringgetClientInfo(String name)Returns the value of the client info property specified by name.intgetHoldability()Retrieves the current holdability of ResultSet objects created using this Connection object.DatabaseMetaDatagetMetaData()Retrieves a DatabaseMetaData object that contains metadata about the database to which this Connection object represents a connection.intgetNetworkTimeout()Retrieves the number of milliseconds the driver will wait for a database request to complete.StringgetSchema()Retrieves this Connection object's current schema name.intgetTransactionIsolation()Retrieves this Connection object's current transaction isolation level.Map 17dc91bb1f