changes

java 数据库编程源代码

# Changelog
# $Id: CHANGES,v 1.2 1998/08/25 04:06:59 mmatthew Exp $

07-04-99 - Better Documentation (in progress), in doc/mm.doc/book1.html

           DBMD now allows null for a column name pattern (not in 
           spec), which it changes to '%'.

           DBMD now has correct types/lengths for getXXX().

           ResultSet.getDate(), getTime(), and getTimestamp() fixes. 
           (contributed by Alan Wilken)

           EscapeProcessor now handles \{ \} and { or } inside quotes
           correctly. (thanks to Alik for some ideas on how to fix it)

           Fixes to properties handling in Connection.
           (contributed by Juho Tikkala)

           ResultSet.getObject() now returns null for NULL columns
           in the table, rather than bombing out.
           (thanks to Ben Grosman)

           ResultSet.getObject() now returns Strings for types
           from MySQL that it doesn't know about. (Suggested by
           Chris Perdue)

           Removed DataInput/Output streams, not needed, 1/2 number
           of method calls per IO operation.

           Use default character encoding if one is not specified. This
           is a work-around for broken JVMs, because according to spec,
           EVERY JVM must support "ISO8859_1", but they don't.

06-03-99 - Fixed Connection to use the platform character encoding
           instead of "ISO8859_1" if one isn't explicitly set. This 
           fixes problems people were having loading the character-
           converter classes that didn't always exist (JVM bug).
           (thanks to Fritz Elfert for pointing out this problem)

05-27-99 - Changed MysqlIO to re-use packets where possible to reduce
           memory usage.

05-13-99 - Fixed escape-processor bugs pertaining to {} inside
           quotes.

04-14-99 - Fixed character-set support for non-Javasoft JVMs
           (thanks to many people for pointing it out)

           Fixed ResultSet.getBoolean() to recognize 'y' & 'n'
           as well as '1' & '0' as boolean flags.
           (thanks to Tim Pizey)

           Fixed ResultSet.getTimestamp() to give better performance.
           (thanks to Richard Swift)

           Fixed getByte() for numeric types.
           (thanks to Ray Bellis)

           Fixed DatabaseMetaData.getTypeInfo() for DATE type.
           (thanks to Paul Johnston)

           Fixed EscapeProcessor for "fn" calls.
	   (thanks to Piyush Shah at locomotive.org)

           Fixed EscapeProcessor to not do extraneous work if there
           are no escape codes.
           (thanks to Ryan Gustafson)

           Fixed Driver to parse URLs of the form "jdbc:mysql://host:port"
           (thanks to Richard Lobb)

03-24-99 - Fixed Timestamps for PreparedStatements
    
           Fixed null pointer exceptions in RSMD and RS

           Re-compiled with jikes for valid class files (thanks ms!)

03-08-99 - Fixed escape processor to deal with un-matched { and }
           (thanks to Craig Coles)
           
           Fixed escape processor to create more portable (between
           DATETIME and TIMESTAMP types) representations so that
           it will work with BETWEEN clauses.
           (thanks to Craig Longman)
           
           MysqlIO.quit() now closes the socket connection. Before,
           after many failed connections some OS's would run out
           of file descriptors. (thanks to Michael Brinkman)
           
           Fixed NullPointerException in Driver.getPropertyInfo.
           (thanks to Dave Potts)
            
           Fixes to MysqlDefs to allow all *text fields to be
           retrieved as Strings.
           (thanks to Chris at Leverage)
           
           Fixed setDouble in PreparedStatement for large numbers
           to avoid sending scientific notation to the database.
           (thanks to J.S. Ferguson)
           
           Fixed getScale() and getPrecision() in RSMD.
           (contrib'd by James Klicman)
           
           Fixed getObject() when field was DECIMAL or NUMERIC
           (thanks to Bert Hobbs)
           
           DBMD.getTables() bombed when passed a null table-name
           pattern. Fixed. (thanks to Richard Lobb)
           
           Added check for "client not authorized" errors during
           connect. (thanks to Hannes Wallnoefer)
           
02-19-99 - Result set rows are now byte arrays. Blobs and Unicode
           work bidriectonally now. The useUnicode and encoding
           options are implemented now.
           
           Fixes to PreparedStatement to send binary set by
           setXXXStream to be sent un-touched to the MySQL server.
           
           Fixes to getDriverPropertyInfo().
           
12-31-98 - Changed all ResultSet fields to Strings, this should allow
           Unicode to work, but your JVM must be able to convert
           between the character sets. This should also make reading
           data from the server be a bit quicker, because there is now
           no conversion from StringBuffer to String.

           Changed PreparedStatement.streamToString() to be more
           efficient (code from Uwe Schaefer).

	     URL parsing is more robust (throws SQL exceptions on errors
           rather than NullPointerExceptions)

           PreparedStatement now can convert Strings to Time/Date values
           via setObject() (code from Robert Currey).

	     IO no longer hangs in Buffer.readInt(), that bug was
           introduced in 1.1d when changing to all byte-arrays for
           result sets. (Pointed out by Samo Login)

11-03-98 - Fixes to DatabaseMetaData to allow both IBM VA and J-Builder
           to work. Let me know how it goes. (thanks to Jac Kersing)

	     Fix to ResultSet.getBoolean() for NULL strings 
	     (thanks to Barry Lagerweij)

	     Beginning of code cleanup, and formatting. Getting ready
	     to branch this off to a parallel JDBC-2.0 source tree.

           Added "final" modifier to critical sections in MysqlIO and
           Buffer to allow compiler to inline methods for speed.

9-29-98 - If object references passed to setXXX() in PreparedStatement are
          null, setNull() is automatically called for you. (Thanks for the
          suggestion goes to Erik Ostrom)

          setObject() in PreparedStatement will now attempt to write a 
          serialized  representation of the object to the database for
          objects of Types.OTHER and objects of unknown type.

          Util now has a static method readObject() which given a ResultSet
          and a column index will re-instantiate an object serialized in
          the above manner.

9-02-98 - Got rid of "ugly hack" in MysqlIO.nextRow(). Rather than
          catch an exception, Buffer.isLastDataPacket() was fixed.
          
          Connection.getCatalog() and Connection.setCatalog()
          should work now.

          Statement.setMaxRows() works, as well as setting
          by property maxRows. Statement.setMaxRows() overrides
          maxRows set via properties or url parameters.

	  Automatic re-connection is available. Because it has
          to "ping" the database before each query, it is
          turned off by default. To use it, pass in "autoReconnect=true"
          in the connection URL. You may also change the number of
          reconnect tries, and the initial timeout value via 
          "maxReconnects=n" (default 3) and "initialTimeout=n" 
          (seconds, default 2) parameters. The timeout is an 
          exponential backoff type of timeout, e.g. if you have initial 
          timeout of 2 seconds, and maxReconnects of 3, then the driver
          will timeout 2 seconds, 4 seconds, then 16 seconds between each
          re-connection attempt.

8-24-98 - Fixed handling of blob data in Buffer.java
	
	  Fixed bug with authentication packet being
	  sized too small.

	  The JDBC Driver is now under the LPGL to allow 
          people to legally include it in their non-GPL'd 
          software.
	
8-14-98 - Fixed Buffer.readLenString() to correctly
          read data for BLOBS.
          
          Fixed PreparedStatement.stringToStream to
          correctly read data for BLOBS.
          
          Fixed PreparedStatement.setDate() to not
          add a day.
          
          (above fixes thanks to Vincent Partington)
          
          Added URL parameter parsing (?user=... etc).
          
          (thanks to Sander Magi).

8-04-98 - Big news! New package name. Tim Endres from ICE
          Engineering is starting a new source tree for
          GNU GPL'd Java software. He's graciously given
          me the org.gjt.mm package directory to use, so now 
          the driver is in the org.gjt.mm.mysql package scheme.
          I'm "legal" now. Look for more information on Tim's
          project soon.
          
          Now using dynamically sized packets to reduce
          memory usage when sending commands to the DB.
          
          Small fixes to getTypeInfo() for parameters, etc.
          
          DatabaseMetaData is now fully implemented. Let me
          know if these drivers work with the various IDEs
          out there. I've heard that they're working with
          JBuilder right now.
          
          Added JavaDoc documentation to the package.
          
          Package now available in .zip or .tar.gz.
          
7-29-98 - Implemented getTypeInfo(). 
          Connection.rollback() now throws an SQLException
          per the JDBC spec.

7-28-98 - Added PreparedStatement that supports all JDBC API
          methods for PreparedStatement including InputStreams.
          Please check this out and let me know if anything is
          broken.
          
          Fixed a bug in ResultSet that would break some
          queries that only returned 1 row.
          
          Fixed bugs in DatabaseMetaData.getTables(), 
          DatabaseMetaData.getColumns() and
          DatabaseMetaData.getCatalogs().
          
          Added functionality to Statement that allows
          executeUpdate() to store values for IDs that are
          automatically generated for AUTO_INCREMENT fields.
          Basically, after an executeUpdate(), look at the
          SQLWarnings for warnings like "LAST_INSERTED_ID =
          'some number', COMMAND = 'your SQL query'".
          
          If you are using AUTO_INCREMENT fields in your
          tables and are executing a lot of executeUpdate()s
          on one Statement, be sure to clearWarnings() every
          so often to save memory.

7-06-98 - Split MysqlIO and Buffer to separate classes. Some
          ClassLoaders gave an IllegalAccess error for some
          fields in those two classes. Now mm.mysql works in 
          applets and all classloaders.

          Thanks to Joe Ennis <[e-mail]> for pointing
          out the problem and working on a fix with me.

7-01-98 - Fixed DatabaseMetadata problems in getColumns() and
          bug in switch statement in the Field constructor.

          Thanks to Costin Manolache <[e-mail]> for 
          pointing these out.

5-21-98 - Incorporated efficiency changes from 
          Richard Swift <[e-mail]> in
          MysqlIO.java and ResultSet.java

          We're now 15% faster than gwe's driver.

          Started working on DatabaseMetaData.
          
          The following methods are implemented:
           * getTables() 
           * getTableTypes()
           * getColumns
           * getCatalogs()