Changes in This Release for Oracle Database JDBC Developer's Guide

New Features

The following features are new in this release:

• Support for Row Count Per Iteration for Array DMLs

  See "Row Count per Iteration for Array DMLs" section.

• Support for Application Continuity

  See Chapter 27, "Application Continuity for Java".

• Support for Transaction Guard

  See Chapter 26, "Transaction Guard for Java".

• Database Resident Connection Pooling

  See Chapter 23, "Database Resident Connection Pooling".

• Support for Latest JDBC Standard

  See "Support for JDBC 4.1 Standard" section.

• Support for SHA-2 in Oracle Advanced Security

  See "Support for Oracle Advanced Security" section.

• Support for the O7L_MR Client Ability

  See "Support for Login Authentication" section.

• Support for Implicit Results

  See "Support for Implicit Results" section.

• Support for Invisible Columns

  See "Working with Invisible Columns" section.

• Support for PL/SQL Package Types as Parameters

  See "Using PL/SQL Types" section.

• Support for Monitoring of Database Operations

  See "Monitoring Database Operations" section.

• Support for Promoting a Local Transaction to a Global Transaction

  See "OracleXAResource Method Functionality and Input Parameters".

• Support for the ? character used in the MATCH_RECOGNIZE clause

  See "MATCH_RECOGNIZE Clause" section .

• Support for specifying delay between connection retries

  See "Support for Delay in Connection Retries" section.

• Support for Increased Length Limit for Various Data Types

  Starting from this release, there is an increase in the length limit for VARCHAR2, NVARCHAR2, and RAW data types in Oracle SQL to 32767 (32K) bytes. For NVARCHAR columns, the limit is 32766 bytes.

  For using these data types with extended size, you must perform the following steps:

  1. Set the COMPATIBLE initialization parameter to 12.0.0.0.

  2. Set the MAX_STRING_SIZE initialization parameter to EXTENDED.

  3. Run the rdbms/admin/utl32k.sql script.

  See Also:

  Oracle Database Reference for more information about using these data types with extended size

Multitenant Data Source for Java

To enable sharing a common pool of connections across multiple PDBs (or tenants), Oracle JDBC and Universal Connection Pool (UCP) furnish the multitenant data source for Java. In Oracle Database 12c Release 1 (12.1), it is based on a combination of the following:

• Global database user (with access privileges to any PDB)

• UCP connection labeling

• The new SET CONTAINER statement within a callback function:

  The advantage of the SET CONTAINER statement is that the pool does not have to create a new connection to a PDB, if there is an existing connection to a different PDB. The pool can use the existing connection and can connect to the desired PDB through the SET CONTAINER statement. Use the following command to achieve this:

  ALTER SESSION SET CONTAINER=<PDB Name>
  

  This feature avoids the need to create a new connection from scratch.

• The UCP connection labeling callback interface.

Example

Following steps describe how mutlitenant data source for Java works:

1. Suppose, you have Tenant1, who calls the getConnection method with the corresponding label (mapped to the database ID) for a connection to PDB1.

2. UCP searches the pool for a free connection, tentatively with the specified label mapped to the database ID.

3. If for a connection Conn1, the label reads PDB1, then it is passed to JDBC, and consequently to Tenant1 for using the connection.

   Otherwise, if no connection label reads PDB1, then the following steps are performed:

   1. UCP invokes the user-implemented configure callback method to set the connection to PDB1 using the ALTER SESSION SET CONTAINER command.

   2. The SET CONTAINER statement is passed to the server and parsed.

   3. The server executes the SET CONTAINER statement and assigns the PDB-specific role to Tenant1^Foot 1 .

   4. The server then connects Conn1 to PDB1, and returns the corresponding database ID (dbid) and other properties to JDBC.

   5. JDBC notifies UCP and passes Conn1 to Tenant1 for using the connection.

   See Also:

   http://www.oracle.com/technetwork/database/application-development/index-099369.html

Deprecated Features

The following features are deprecated in this release, and may be desupported in a future release:

• Concrete classes in the oracle.sql package

  The concrete classes in the oracle.sql package are deprecated. Use the new JDBC interfaces instead of these classes.

  See MoS Note 1364193.1 for more information about these interfaces.

• defineColumnType method

  Most of the variants of the defineColumnType method are deprecated. The supported variants are for:

  • LOB to LONG conversions

  • Configure the LOB prefetch size

  See the JDBC Javadoc for more information.

• CONNECTION_PROPERTY_STREAM_CHUNK_SIZE property

  See the JDBC Javadoc for more information.

• Oracle Update Batching

  Oracle update batching is deprecated from this release in favor of standard update batching.

  See "Standard Update Batching" section for more information.

• EndToEndMetrics related APIs

  EndToEndMetrics related APIs are deprecated in this release.

  See Chapter 33, "JDBC DMS Metrics" for more information.

Desupported Features

The following features are no longer supported by Oracle. See Oracle Database Upgrade Guide for a complete list of desupported features in this release.

• Implicit Connection Caching

Other Changes

The following are additional changes in the release:

• Run-Time Connection Load Balancing

  The Run-Time Connection Load Balancing feature enables routing of work requests to an instance that offers the best performance, minimizing the need to relocate work. With the desupport of Implicit Connection Cache, Oracle recommends you to use this feature with Universal Connection Pool. So, the Run-Time Connection Load Balancing chapter is removed from the book from this release.

  See Oracle Universal Connection Pool for JDBC Developer's Guide for more information about this feature.

• Fast Connection Failover

  Fast Connection Failover offers a driver-independent way for your Java Database Connectivity (JDBC) application to take advantage of the connection failover facilities offered by Oracle Database 12c Release 1 (12.1). With the desupport of Implicit Connection Cache, Oracle recommends you to use this feature with Universal Connection Pool. So, the Fast Connection Failover chapter is removed from the book from this release.

  See Oracle Universal Connection Pool for JDBC Developer's Guide for more information about this feature.