readme_jdbc.txt

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Setting Up Your Environment
---------------------------

On Win95/Win98/NT:
  - Add [ORACLE_HOME]\jdbc\lib\classes111.zip and
    [ORACLE_HOME]\jdbc\lib\nls_charset11.zip to your CLASSPATH.
    (Add classes12.zip and nls_charset12.zip if JDK 1.2.x or 1.3 is
    used. Add ojdbc14.jar and nls_charset12.zip if JDK 1.4 is used.)
  - Make sure [ORACLE_HOME]\bin is in your PATH.

On Solaris/Digital Unix:
  - Add [ORACLE_HOME]/jdbc/lib/classes111.zip and
    [ORACLE_HOME]/jdbc/lib/nls_charset11.zip to your CLASSPATH.
    (Add classes12.zip and nls_charset12.zip if JDK 1.2.x or 1.3 is
     used. Add ojdbc14.jar and nls_charset12.zip if JDK 1.4 is used.)
  - Add [ORACLE_HOME]/jdbc/lib to your LD_LIBRARY_PATH.

On HP/UX:
  - Add [ORACLE_HOME]/jdbc/lib/classes111.zip and
    [ORACLE_HOME]/jdbc/lib/nls_charset11.zip to your CLASSPATH.
    (Add classes12.zip and nls_charset12.zip if JDK 1.2.x or 1.3 is
    used. Add ojdbc14.jar and nls_charset12.zip if JDK 1.4 is used.)
  - Add [ORACLE_HOME]/jdbc/lib to your SHLIB_PATH and LD_LIBRARY_PATH.

On AIX:
  - Add [ORACLE_HOME]/jdbc/lib/classes111.zip and
    [ORACLE_HOME]/jdbc/lib/nls_charset11.zip to your CLASSPATH.
    (Add classes12.zip and nls_charset12.zip if JDK 1.2.x 1.3 is
     used.  Add ojdbc14.jar and nls_charset12.zip if JDK 1.4 is used.)
  - Add [ORACLE_HOME]/jdbc/lib to your LIBPATH and LD_LIBRARY_PATH.


Some Useful Hints In Using the JDBC Drivers
-------------------------------------------

Please refer to "JDBC Developer's Guide and Reference" for details
regarding usage of Oracle's JDBC Drivers.  This section only offers
useful hints.  These hints are not meant to be exhaustive.

These are a few simple things that you should do in your JDBC program:

 1. Import the necessary JDBC classes in your programs that use JDBC.
    For example:

      import java.sql.*;
      import java.math.*;

 2. Register the Oracle driver before before calling other JDBC APIs.
    (This is not needed if you are using the JDBC Server-side Internal
    Driver because registration is done automatically in the server.)
    To register the Oracle driver, make sure the following statement
    is executed at least once in your Java session:

      DriverManager.registerDriver(
        new oracle.jdbc.OracleDriver());

 3. Open a connection to the database with the getConnection call.
    Different connection URLs should be used for different JDBC
    drivers.  The following examples demonstrate the different URLs.

    For the JDBC OCI Driver:

      Connection conn = DriverManager.getConnection(
                          "jdbc:oracle:oci:@<database>",
                          "my_user", "my_password");

      where <database> is either an entry in tnsnames.ora or a SQL*net
      name-value pair.

    For the JDBC Thin Driver, or Server-side Thin Driver:

      Connection conn = DriverManager.getConnection(
                          "jdbc:oracle:thin:@<database>",
                          "my_user", "my_password");

      where <database> is either a string of the form
      <host>:<port>:<sid>,  a SQL*net name-value pair, or a service
      name. 

    For the JDBC Server-side Internal Driver:

      Connection conn = DriverManager.getConnection(
                          "jdbc:oracle:kprb:");

      Note that the trailing ':' character is necessary.  When you use
      the Server-side Internal Driver, you always connect to the
      database you are executing in.  You can also do this:

      Connection conn
        = new oracle.jdbc.OracleDriver().defaultConnection();


New Package oracle.jdbc
-----------------------

Beginning in Oracle 9i, the Oracle extensions to JDBC are captured in
the package oracle.jdbc. This package contains classes and interfaces
that specify the Oracle extensions in a manner similar to the way the
classes and interfaces in java.sql specify the public JDBC API.

Your code should use the package oracle.jdbc instead of the package
oracle.jdbc.driver used in earlier versions of Oracle. Use of the
package oracle.jdbc.driver is now deprecated, but will be supported
for backwards compatibility.

All that is required to covert your code is to replace
"oracle.jdbc.driver" with "oracle.jdbc" in the source and
recompile. This cannot be done piecewise. You must convert all classes
and interfaces that are referenced by an application. Conversion is
not required, but is highly recommended. Future releases of Oracle will
have features that are incompatible with use of the package
oracle.jdbc.driver.

The purpose of this change in to enable the Oracle JDBC drivers to
have multiple implementations. In all releases up to and including
Oracle 9i, all of the Oracle JDBC drivers have used the same top level
implementation classes, the classes in the package
oracle.jdbc.driver. By converting your code to use oracle.jdbc, you
will be able to take advantage of future enhancements that use
different implementation classes. There are no such enhancements in
Oracle 9i, but there are plans for such enhancements in the future.

Additionally, these interfaces permit the use of some code patterns
that are difficult to use when your code uses the package
oracle.jdbc.driver. For example, you can more easily develop wrapper
classes for the Oracle JDBC classes. If you wished to wrap the
OracleStatement class in order to log all SQL statements, you could
easily do so by creating a class that wraps OracleStatment. That class
would implement the interface oracle.jdbc.OracleStatement and hold an
oracle.jdbc.OracleStatement as an instance variable. This wrapping
pattern is much more difficult when your code uses the package
oracle.jdbc.driver as you cannot extend the class
oracle.jdbc.driver.OracleStatement. In implementing a Connection
wrapper class, you should either inherit from the class
oracle.jdbc.OracleConnectionWrapper, or base your class on that class.
The source for oracle.jdbc.OracleConnectionWrapper is included in the
demos directory.

Once again, your code should use the new package oracle.jdbc instead
of the package oracle.jdbc.driver. Conversion is not required as
oracle.jdbc.driver will continue to be supported for backwards
compatibility. Conversion is highly recommended as there will in later
releases be features that are not supported if your code uses
oracle.jdbc.driver.


Java Stored Procedures
----------------------

Please note that examples for callins and instance methods using Oracle
8 Object Types are provided in:

  [ORACLE_HOME]/javavm/demo/demo.zip

Once unzipped, the directory containing the examples is:

  [ORACLE_HOME]/javavm/demo/examples/jsp


Known Problems/Limitations In This Release
------------------------------------------

The following is a list of known problems/limitations:

 *  There is a limitation regarding the use of stream input for LOB
    types.  Stream input for LOB types can only be used for 8.1.7 or
    later JDBC OCI driver connecting to an 8.1.7 or later Oracle
    server.  The use of stream input for LOB types in all other
    configurations may result in data corruption.  PreparedStatement
    stream input APIs include: setBinaryStream(), setAsciiStream(),
    setUnicodeStream(), setCharacterStream() and setObject().

 *  Programs can fail to open 16 or more connections using our
    client-side drivers at any one time.  This is not a limitation 
    caused by the JDBC drivers.  It is most likely that the limit of
    per-process file descriptors is exceeded.  The solution is to 
    increase the limit. 

 *  The Server-side Internal Driver has the following limitation:
    - Data access for LONG and LONG RAW types is limited to 32K of
      data.
    - Inserts of Object Types (Oracle Objects, Collections and
      References) will not work when the database compatibility mode
      is set to 8.0.  This limitation does not apply when the
      compatibility mode is set to 8.1.
    - In a chain of SQLExceptions, only the first one in the chain
      will have a getSQLState value.
    - Batch updates with Oracle 8 Object, REF and Collection data
      types are not supported.

 *  The JDBC OCI driver on an SSL connection hangs when the Java
    Virtual Machine is running in green threads mode.  A work-around
    is to run the Java Virtual Machine in native threads mode.

 *  Date-time format, currency symbol and decimal symbols are always
    presented in American convention.

 *  When using OracleStatement.defineColumnType(), it is not necessary
    to define the column type to be the same as the column type
    declared in the database.  If the types are different, the
    retrieved values are converted to the type specified in
    defineColumnType.

    Note:  Most reasonable conversions work, but not all. If you find
    a conversion that you think is reasonable, but that does not work,
    please submit a TAR to Oracle Support.

 *  The utility dbms_java.set_output or dbms_java.set_stream that is
    used for redirecting the System.out.println() in JSPs to stdout
    SHOULD NOT be used when JDBC tracing is turned on.  This is
    because the current implementation of dbms_java.set_output and
    set_stream uses JDBC to write the output to stdout.  The result
    would be an infinite loop.

 *  The JDBC OCI and Thin drivers do not read CHAR data via binary
    streams correctly.  In other word, using getBinaryStream() to
    retrieve CHAR data may yield incorrect results.  A work-around is
    to use either getCHAR() or getAsciiStream() instead.  The other
    alternative is to use getUnicodeStream() although the method is
    deprecated.

BUG-899078 (since 8.1.6)
    The JDBC Server-side Internal driver has extra space padding with
    PL/SQL CHAR OUT (2 to 3 space depending on character set).
    Problem occurs in most of the multibyte database character set
    except UTF8.

 *  There is a limitation for Triggers implemented in Java and Object
    Types.  It only affects the IN argument types of triggers
    implemented using Java on the client-side.  The restriction does
    not apply to JDBC programs running inside the server.  Triggers
    implemented as Java methods cannot have IN arguments of Oracle 8
    Object or Collection type.  This means the Java methods used to
    implement triggers cannot have arguments of the following types:

    - java.sql.Struct
    - java.sql.Array
    - oracle.sql.STRUCT
    - oracle.sql.ARRAY
    - oracle.jdbc2.Struct
    - oracle.jdbc2.Array
    - any class implementing oracle.jdbc2.SQLData or
      oracle.sql.CustomDatum

 *  The scrollable result set implementation has the following
    limitation:

    - setFetchDirection() on ScrollableResultSet does not do anything.
    - refreshRow() on ScrollableResultSet does not support all
      combinations of sensitivity and concurrency.  The following
      table depicts the supported combinations.

        Support     Type                       Concurrency
        -------------------------------------------------------
        no          TYPE_FORWARD_ONLY          CONCUR_READ_ONLY
        no          TYPE_FORWARD_ONLY          CONCUR_UPDATABLE
        no          TYPE_SCROLL_INSENSITIVE    CONCUR_READ_ONLY
        yes         TYPE_SCROLL_INSENSITIVE    CONCUR_UPDATABLE
        yes         TYPE_SCROLL_SENSITIVE      CONCUR_READ_ONLY
        yes         TYPE_SCROLL_SENSITIVE      CONCUR_UPDATABLE

BUG-1516862 (since 9.0.0)
    Passing an OPAQUE type as an argument to a Java Stored Procedure
    does not work.

BUG-1542130 (since 9.0.0)
    The use of OciConnectionPool may cause a hang in a multi-threaded
    environment.

BUG-1640110 (since 9.0.0)
    The JDBC OCI driver may hang when executing a query with invalid
    double quotes in the query string.  This problem only occurs when
    the NLS_LANG environment variable is set.

 *  Access to the new Datetime datatypes is only supported in the
    Jdbc Thin driver with JDK 1.2, 1.3 and 1.4.  These Datetime data
    types inlcude: TIMESTAMP, TIMESTAMPTZ and TIMESTAMPLTZ.  In 
    addition, String APIs like PreparedStatement.setString() and
    Resultset.getString() do not work for these data types.  Users
    must use setTIMESTAMP*() and getTIMESTAMP*().

BUG-2171766 (since 9.2.0)
    When writing JDBC code that contains SQL method invocations,
    the syntax " ?.method(args,...) " results in the SQL error
    message: ORA-01036: illegal variable name/number. This message
    is somewhat misleading. What is required is that the ? must be
    followed by a " " (space) to avoid this issue.

BUG-2165794 (since 9.2.0)
    DBC XA applications needing to use TMSUSPEND & TMRESUME features
    need to use the TMNOMIGRATE FLAG. If this flag is not used, the
    application may @receive Error ORA 1002: fetch out of sequence.

BUG-2158394 (since 9.2.0)
    ORA-6505 when setting null to char column via stored procedure 
    using setNull() method with java.sql.Types.CHAR. Using
    java.sql.Types.VARCHAR, is ok. Only occurs with Thin driver and
    JA16SJIS or JA16EUC character sets. 

BUG-2148328 (since 9.2.0)
    On Linux, SJIS data in table names  are returned as replacement
    characters with JDK1.2 and JDK1.3 with both the Thin and OCI
    drivers. This is due to a bug in the JDKs. The workaround is to
    use JDK 1.1.8, which does not have this bug.

BUG-2144602 (since 8.1.7)
    When running Windows2000 with the locale set to Chinese (Taiwan)
    and the character set set to ZHT16DBT, all Chinese characters
    are displayed as "?".

BUG-2130384 (since 9.0.1)
    Does not raise ORA-22814 as it should when inserting too large
    of an element value into a VARRAY using setARRAY.

BUG-2249191
    In the Server Internal Driver, setting the query timeout does not
    (and likely will never) work. The query execution will not be
    canceled when the timeout expires, even if the query runs forever.
    Further, after the query returns, the execution of your code
    may pause for the length of the timeout.

BUG-2213820
    OracleConnectionCacheImpl cannot be serialized because it has a
    member that is not serializable. This causes some problems with
    JSPs that store the connection cache as a bean in session scope.

BUG-2180673
    When using OracleOCIConnectionPool, the methods getPoolSize and
    getActiveSize return the wrong results. getPoolSize always returns
    minLimit and getActiveSize always returns 0.

BUG-1910217
    TIMESTAMPs are not supported in ADTs.

BUG-2245502
    If you use the Thin driver to connect to an 8.1.7 database, and 
    then attempt to access a 7.3.4 database via DBLinks using bind
    variables, the values of the bind variables may be swapped.

BUG-2183691
    The insertRow method on an updateable result set inserts the row
    into the database, but does not insert it into the result set
    itself. 

BUG-2095829
    In the Server Internal Driver, calling a PL/SQL procedure and 
    passing a NULL value to an argument of a user defined type fails.
    In some cases the session hangs, in others you will get ora-3113, 
    ora-3114, or ora-24323.

BUG-1568923 
    Using the OCI driver, using setBytes to insert more than 50K into
    a LONG RAW truncates the inserted value.

BUG-2285052 (since 9.2.0.1)
    Extra space and null characters are returned by ResultSet.getString()
    and Scrollable ResultSet getString() for NCHAR column when the 
    database national character set is UTF8.  This behavior occurs only
    with JDBC THIN driver.