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17        <tr>
18          <th colspan="3" align="center">Berkeley DB 4.5.20 Change Log</th>
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27    </div>
28    <div class="sect1" lang="en" xml:lang="en">
29      <div class="titlepage">
30        <div>
31          <div>
32            <h2 class="title" style="clear: both"><a id="changelog_4_5_20"></a>Berkeley DB 4.5.20 Change Log</h2>
33          </div>
34        </div>
35      </div>
36      <div class="toc">
37        <dl>
38          <dt>
39            <span class="sect2">
40              <a href="changelog_4_5_20.html#id1652081">Database or Log File On-Disk Format Changes:</a>
41            </span>
42          </dt>
43          <dt>
44            <span class="sect2">
45              <a href="changelog_4_5_20.html#id1652140">New Features:</a>
46            </span>
47          </dt>
48          <dt>
49            <span class="sect2">
50              <a href="changelog_4_5_20.html#id1652228">Database Environment Changes:</a>
51            </span>
52          </dt>
53          <dt>
54            <span class="sect2">
55              <a href="changelog_4_5_20.html#id1652258">Concurrent Data Store Changes:</a>
56            </span>
57          </dt>
58          <dt>
59            <span class="sect2">
60              <a href="changelog_4_5_20.html#id1652087">General Access Method Changes:</a>
61            </span>
62          </dt>
63          <dt>
64            <span class="sect2">
65              <a href="changelog_4_5_20.html#id1652299">Btree Access Method Changes:</a>
66            </span>
67          </dt>
68          <dt>
69            <span class="sect2">
70              <a href="changelog_4_5_20.html#id1652313">Hash Access Method Changes:</a>
71            </span>
72          </dt>
73          <dt>
74            <span class="sect2">
75              <a href="changelog_4_5_20.html#id1652102">Queue Access Method Changes:</a>
76            </span>
77          </dt>
78          <dt>
79            <span class="sect2">
80              <a href="changelog_4_5_20.html#id1652245">Recno Access Method Changes:</a>
81            </span>
82          </dt>
83          <dt>
84            <span class="sect2">
85              <a href="changelog_4_5_20.html#id1652253">C++-specific API Changes:</a>
86            </span>
87          </dt>
88          <dt>
89            <span class="sect2">
90              <a href="changelog_4_5_20.html#id1652294">Java-specific API Changes:</a>
91            </span>
92          </dt>
93          <dt>
94            <span class="sect2">
95              <a href="changelog_4_5_20.html#id1652112">Java collections and bind API Changes:</a>
96            </span>
97          </dt>
98          <dt>
99            <span class="sect2">
100              <a href="changelog_4_5_20.html#id1652394">Tcl-specific API Changes:</a>
101            </span>
102          </dt>
103          <dt>
104            <span class="sect2">
105              <a href="changelog_4_5_20.html#id1652384">RPC-specific Client/Server Changes:</a>
106            </span>
107          </dt>
108          <dt>
109            <span class="sect2">
110              <a href="changelog_4_5_20.html#id1652261">Replication Changes:</a>
111            </span>
112          </dt>
113          <dt>
114            <span class="sect2">
115              <a href="changelog_4_5_20.html#id1652360">XA Resource Manager Changes:</a>
116            </span>
117          </dt>
118          <dt>
119            <span class="sect2">
120              <a href="changelog_4_5_20.html#id1652538">Locking Subsystem Changes:</a>
121            </span>
122          </dt>
123          <dt>
124            <span class="sect2">
125              <a href="changelog_4_5_20.html#id1652623">Logging Subsystem Changes:</a>
126            </span>
127          </dt>
128          <dt>
129            <span class="sect2">
130              <a href="changelog_4_5_20.html#id1652634">Memory Pool Subsystem Changes:</a>
131            </span>
132          </dt>
133          <dt>
134            <span class="sect2">
135              <a href="changelog_4_5_20.html#id1652533">Transaction Subsystem Changes:</a>
136            </span>
137          </dt>
138          <dt>
139            <span class="sect2">
140              <a href="changelog_4_5_20.html#id1652629">Utility Changes:</a>
141            </span>
142          </dt>
143          <dt>
144            <span class="sect2">
145              <a href="changelog_4_5_20.html#id1652610">Configuration, Documentation, Portability and Build Changes:</a>
146            </span>
147          </dt>
148        </dl>
149      </div>
150      <div class="sect2" lang="en" xml:lang="en">
151        <div class="titlepage">
152          <div>
153            <div>
154              <h3 class="title"><a id="id1652081"></a>Database or Log File On-Disk Format Changes:</h3>
155            </div>
156          </div>
157        </div>
158        <div class="orderedlist">
159          <ol type="1">
160            <li>The on-disk log format has changed.</li>
161          </ol>
162        </div>
163      </div>
164      <div class="sect2" lang="en" xml:lang="en">
165        <div class="titlepage">
166          <div>
167            <div>
168              <h3 class="title"><a id="id1652140"></a>New Features:</h3>
169            </div>
170          </div>
171        </div>
172        <div class="orderedlist">
173          <ol type="1">
174            <li>Multi-Version Concurrency Control for the Btree/Recno access
175	methods.</li>
176            <li>A new replication framework with a default TCP/IP setup.</li>
177            <li>Online replication upgrades for high availability replicated 24/7
178	systems.</li>
179            <li>A new event-style notification.</li>
180            <li>Several enhancements to the Java Collections API including the
181	implementation of the size() method.</li>
182          </ol>
183        </div>
184      </div>
185      <div class="sect2" lang="en" xml:lang="en">
186        <div class="titlepage">
187          <div>
188            <div>
189              <h3 class="title"><a id="id1652228"></a>Database Environment Changes:</h3>
190            </div>
191          </div>
192        </div>
193        <div class="orderedlist">
194          <ol type="1">
195            <li>Update the DB_ENV-&gt;failchk method to garbage collect per-process
196	mutexes stranded after unexpected process failure. [#13964]</li>
197            <li>Fix a bug that could cause memory used to track threads for
198DB_ENV-&gt;failchk to not be reused when a thread no longer exists.
199[#14425]</li>
200            <li>Add set_event_notify behavior as part of new event notification in
201	Berkeley DB. [#14534]</li>
202            <li>Fix a bug so that we no longer panic on DB_ENV-&gt;close() if a
203previous environment close failed to log. This condition will now return
204an error. [#14693]</li>
205            <li>Created os_getenv, removed clib/getenv, implemented Windows specific
206	behavior. [#14942]</li>
207            <li>Fix a bug where it was possible to corrupt the DB_REGISTER
208information file, making it impossible for Berkeley DB applications to
209join database environments. [#14998]</li>
210          </ol>
211        </div>
212      </div>
213      <div class="sect2" lang="en" xml:lang="en">
214        <div class="titlepage">
215          <div>
216            <div>
217              <h3 class="title"><a id="id1652258"></a>Concurrent Data Store Changes:</h3>
218            </div>
219          </div>
220        </div>
221        <div class="orderedlist">
222          <ol type="1">
223            <li>Fix a bug where renaming a subdatabase in a Concurrent Data Store
224	environment could fail. [#14185]</li>
225          </ol>
226        </div>
227      </div>
228      <div class="sect2" lang="en" xml:lang="en">
229        <div class="titlepage">
230          <div>
231            <div>
232              <h3 class="title"><a id="id1652087"></a>General Access Method Changes:</h3>
233            </div>
234          </div>
235        </div>
236        <div class="orderedlist">
237          <ol type="1">
238            <li>Fix a bug that could leave extra unallocated pages at the end of a
239	database file. [#14031]</li>
240            <li>Optimize secondary updates when overwriting primary records.
241	[#14075]</li>
242            <li>Fix a bug to prevent a trap when creating a named in-memory database
243	and there are already temporary files open. [#14133]</li>
244            <li>Fix a bug which caused a trap if the key parameter to DBC-&gt;c_get was
245	omitted with DB_CURRENT. [#14143]</li>
246            <li>Fix a bug with secondary cursors when the secondary has off-page
247duplicates. This bug resulted in incorrect primary data being returned.
248[#14240]</li>
249            <li>Improve performance when removing a subdatabase by not locking every
250	page. [#14366]</li>
251            <li>Fix a bug that would not properly upgrade database files from
252	releases 3.2.9 (and earlier) to releases 4.0 (and greater). [#14461]</li>
253            <li>Fix a bug that could cause a DB_READ_UNCOMMITTED get through a
254	secondary index to return DB_SECONDARY_CORRUPT. [#14487]</li>
255            <li>Fix a bug so that non-transactional cursor updates of a
256	transactional database will generate an error. [#14519]</li>
257            <li>Add a message when the system panics due to a page in the wrong
258	state at its time of allocation. [#14527]</li>
259            <li>Fix a remove failure when attempting to remove a file that is open
260	in another thread of control. [#14780]</li>
261            <li>Fix a bug where the key was not ignored when doing a cursor put with
262	the DB_CURRENT flag. [#14988]</li>
263          </ol>
264        </div>
265      </div>
266      <div class="sect2" lang="en" xml:lang="en">
267        <div class="titlepage">
268          <div>
269            <div>
270              <h3 class="title"><a id="id1652299"></a>Btree Access Method Changes:</h3>
271            </div>
272          </div>
273        </div>
274        <div class="orderedlist">
275          <div class="orderedlist">
276            <ol type="a">
277              <li>When deleting a page don't check the next key in the parent if we
278	are going to delete the parent too.</li>
279              <li>Need to check that the tree has not collapsed between dropping a
280read lock and getting the write lock. If it has collapsed we will fetch
281the root of the tree.</li>
282              <li>Fix a case where we fail to lock the next page before reading it.</li>
283            </ol>
284          </div>
285          <ol type="1">
286            <li>Changed the implementation of internal nodes in btrees so that they
287	no longer share references to overflow pages with leaf nodes. [#10717]</li>
288            <li>Fix a bug that could cause a diagnostic assertion by setting the
289	deleted bit on a record in an internal node. [#13944]</li>
290            <li>Fix three problems in BTREE compaction: [#14238]</li>
291            <li>Fix a bug that could cause the compaction of a Btree with sorted
292duplicates to fail when attempting to compact an off page duplicate tree
293if a key could not fit in an internal node. [#14771]</li>
294            <li>Fix a bug that causes a loop if an empty Btree was compacted.
295	[#14493]</li>
296          </ol>
297        </div>
298      </div>
299      <div class="sect2" lang="en" xml:lang="en">
300        <div class="titlepage">
301          <div>
302            <div>
303              <h3 class="title"><a id="id1652313"></a>Hash Access Method Changes:</h3>
304            </div>
305          </div>
306        </div>
307        <div class="orderedlist">
308          <ol type="1">
309            <li>Fix a bug to allow creation of hash pages during truncate recovery.
310	[#14247]</li>
311          </ol>
312        </div>
313      </div>
314      <div class="sect2" lang="en" xml:lang="en">
315        <div class="titlepage">
316          <div>
317            <div>
318              <h3 class="title"><a id="id1652102"></a>Queue Access Method Changes:</h3>
319            </div>
320          </div>
321        </div>
322        <div class="orderedlist">
323          <ol type="1">
324            <li>Fix a bug where reads of data items outside the range of the queue
325were not kept locked to the end of the transaction, breaking
326serializability. [#13719]</li>
327            <li>Fix a bug that could cause corruption in queue extent files if
328multiple processes tried to open the same extent at the same time.
329[#14438]</li>
330            <li>Improve concurrency for in-place updates in queue databases.
331	[#14918]</li>
332          </ol>
333        </div>
334      </div>
335      <div class="sect2" lang="en" xml:lang="en"><div class="titlepage"><div><div><h3 class="title"><a id="id1652245"></a>Recno Access Method Changes:</h3></div></div></div>
336
337None.
338</div>
339      <div class="sect2" lang="en" xml:lang="en">
340        <div class="titlepage">
341          <div>
342            <div>
343              <h3 class="title"><a id="id1652253"></a>C++-specific API Changes:</h3>
344            </div>
345          </div>
346        </div>
347        <div class="orderedlist">
348          <ol type="1">
349            <li>C++ applications that check the error code in exceptions should note
350that DbMemoryException has been changed to have the error code
351DB_BUFFER_SMALL rather than ENOMEM, to match the error returned by the
352C API. DbMemoryException will be thrown when a Dbt is too small to
353contain data returned by Berkeley DB. When a call to malloc fails, or
354some other resource is exhausted, a plain DbException will be thrown
355with error code set to ENOMEM. [#13939]</li>
356          </ol>
357        </div>
358      </div>
359      <div class="sect2" lang="en" xml:lang="en">
360        <div class="titlepage">
361          <div>
362            <div>
363              <h3 class="title"><a id="id1652294"></a>Java-specific API Changes:</h3>
364            </div>
365          </div>
366        </div>
367        <div class="orderedlist">
368          <ol type="1">
369            <li>Database.verify may now be called. This method is now static and
370	takes a DatabaseConfig parameter. [#13971]</li>
371            <li>Add DB_ENV-&gt;{fileid_reset, lsn_reset} to the public API. [#14076]</li>
372          </ol>
373        </div>
374      </div>
375      <div class="sect2" lang="en" xml:lang="en">
376        <div class="titlepage">
377          <div>
378            <div>
379              <h3 class="title"><a id="id1652112"></a>Java collections and bind API Changes:</h3>
380            </div>
381          </div>
382        </div>
383        <div class="orderedlist">
384          <ol type="1">
385            <li>The com.sleepycat.collections package is now fully compatible with
386	the Java Collections framework. [#14732]</li>
387          </ol>
388        </div>
389      </div>
390      <div class="sect2" lang="en" xml:lang="en">
391        <div class="titlepage">
392          <div>
393            <div>
394              <h3 class="title"><a id="id1652394"></a>Tcl-specific API Changes:</h3>
395            </div>
396          </div>
397        </div>
398        <div class="orderedlist">
399          <ol type="1">
400            <li>Fix a conflicting variable, sysscript.tcl. [#15051]</li>
401          </ol>
402        </div>
403      </div>
404      <div class="sect2" lang="en" xml:lang="en"><div class="titlepage"><div><div><h3 class="title"><a id="id1652384"></a>RPC-specific Client/Server Changes:</h3></div></div></div>
405
406None.
407</div>
408      <div class="sect2" lang="en" xml:lang="en">
409        <div class="titlepage">
410          <div>
411            <div>
412              <h3 class="title"><a id="id1652261"></a>Replication Changes:</h3>
413            </div>
414          </div>
415        </div>
416        <div class="orderedlist">
417          <ol type="1">
418            <li>Fix a bug when running with DEBUG_ROP or DEBUG_WOP. [#13394]</li>
419            <li>Add live replication upgrade support [#13670]</li>
420            <li>Fix a bug so that client databases are removed at the start of
421	internal initialization. [#14147]</li>
422            <li>Fix a bug in replication internal initialization so that data_dir
423will be handled correctly. Make internal initialization resilient to
424multiple data_dir calls with the same directory. [#14489]</li>
425            <li>Fix a bug in the 4.2 sync-up algorithm that could result in no open
426	files. [#14552]</li>
427            <li>Fix a bug when clients decide to re-request. [#14642]</li>
428            <li>Fix a bug where a PERM bulk buffer could have a zero LSN passed to
429	the application callback. [#14675]</li>
430            <li>Change names of some existing replication API methods as described
431in "Replication Method Naming" page of the "Upgrading Berkeley DB
432Applications to Release 4.5" section of Berkeley DB Reference Guide.
433[#14723]</li>
434            <li>Fix a bug which could cause an election to succeed only after
435waiting for the timeout to expire, even when all sites responded in a
436timely manner. The bug was most easily visible in an election between 2
437sites. [#14752]</li>
438            <li>Fix a bug where a process could have an old file handle to a log
439	file. [#14797]</li>
440            <li>Fix a bug where a "log_more" message could be on a log file
441	boundary. [#15034]</li>
442            <li>Fix a bug that could cause log corruption if a database open
443operation were attempted during a call to rep_start in another thread.
444[#15035]</li>
445            <li>Fix a bug during elections where a vote2 arrives before its vote1.
446	[#15055]</li>
447            <li>Fix a bug to make sure we are a client if sending a REP_REREQUEST.
448	[#15066]</li>
449          </ol>
450        </div>
451      </div>
452      <div class="sect2" lang="en" xml:lang="en"><div class="titlepage"><div><div><h3 class="title"><a id="id1652360"></a>XA Resource Manager Changes:</h3></div></div></div>
453
454None.
455</div>
456      <div class="sect2" lang="en" xml:lang="en">
457        <div class="titlepage">
458          <div>
459            <div>
460              <h3 class="title"><a id="id1652538"></a>Locking Subsystem Changes:</h3>
461            </div>
462          </div>
463        </div>
464        <div class="orderedlist">
465          <ol type="1">
466            <li>Fix a bug that could cause a write to hang if DB_READ_UNCOMMITTED
467	is enabled and it tries to reacquire a write lock. [#14919]</li>
468          </ol>
469        </div>
470      </div>
471      <div class="sect2" lang="en" xml:lang="en">
472        <div class="titlepage">
473          <div>
474            <div>
475              <h3 class="title"><a id="id1652623"></a>Logging Subsystem Changes:</h3>
476            </div>
477          </div>
478        </div>
479        <div class="orderedlist">
480          <ol type="1">
481            <li>Fix a bug so that log headers are now included in the checksum. This
482	avoids a possible race in doing hot backups. [#11636].</li>
483            <li>Add a check so that some log sequence errors are diagnosed at run
484	time rather than during recovery. [#13231]</li>
485            <li>Fix a bug where recovery fails if there is no disk space for the
486	forced checkpoint that occurs at the end of processing the log. [#13986]</li>
487            <li>Fix a bug which could cause a page to be missing from the end of a
488database file if the page at the end of the file was freed while it
489contained data and the system was restarted before the log record for
490that free was flushed to disk. [#14090]</li>
491            <li>Fix a bug that could cause log files to be incorrectly removed by
492	log_archive if it was run immediately after recovery. [#14874]</li>
493          </ol>
494        </div>
495      </div>
496      <div class="sect2" lang="en" xml:lang="en">
497        <div class="titlepage">
498          <div>
499            <div>
500              <h3 class="title"><a id="id1652634"></a>Memory Pool Subsystem Changes:</h3>
501            </div>
502          </div>
503        </div>
504        <div class="orderedlist">
505          <ol type="1">
506            <li>Fix a bug that could cause corruption to the buffer pool cache if a
507	race condition was hit while using DB-&gt;compact. [#14360]</li>
508            <li>Fix a bug where cache pages could be leaked in applications creating
509	temporary files for which the DB_MPOOL_NOFILE flag was set. [#14544]</li>
510          </ol>
511        </div>
512      </div>
513      <div class="sect2" lang="en" xml:lang="en">
514        <div class="titlepage">
515          <div>
516            <div>
517              <h3 class="title"><a id="id1652533"></a>Transaction Subsystem Changes:</h3>
518            </div>
519          </div>
520        </div>
521        <div class="orderedlist">
522          <ol type="1">
523            <li>Fix a bug that could cause extra empty pages to appear in a database
524	file after recovery. [#11118]</li>
525            <li>Fix a bug triggered when running recovery with a feedback function
526	that could cause a NULL pointer dereference. [#13834]</li>
527            <li>Fix a bug where running recovery could create duplicate entries in
528	the data directory list. [#13884]</li>
529            <li>Fix a bug to not trade locks if a write lock is already owned.
530	[#13917]</li>
531            <li>Fix a bug that could cause traps or hangs if the DB_TXN-&gt;set_name
532	function is used in a multithreaded application. [#14033]</li>
533            <li>Fix a bug so that a transaction can no longer be committed after it
534	had deadlocked. [#14037]</li>
535            <li>Fix a bug that could cause a trap during recovery if multiple
536	operations that could remove the same extent are recovered. [#14061]</li>
537            <li>Fix a bug that could cause an extent file to be deleted after the
538last record in the extent was consumed but the consuming transaction was
539aborted. [#14179]</li>
540            <li>Fix a bug where the parent database would not use
541	DB_READ_UNCOMMITTED in certain cases when calling DBC-&gt;c_pget. [#14361]</li>
542            <li>Fix a bug so that it is no longer possible to do a non-transactional
543	cursor update on a database that is opened transactionally. [#14519]</li>
544            <li>Fix a bug that causes a sequence to ignore the DB_AUTO_COMMIT
545	settings. [#14582]</li>
546            <li>Fix a bug, change txn_recover so that multiple processes will
547recover prepared transactions without requiring that the first process
548stay active. [#14707]</li>
549            <li>Fix a bug that could cause the wrong record to be deleted if a
550transaction had a cursor on a record with a pending delete and then
551replaced a record that contained overflow data or replaced a record with
552overflow data and that replace failed. [#14834]</li>
553          </ol>
554        </div>
555      </div>
556      <div class="sect2" lang="en" xml:lang="en">
557        <div class="titlepage">
558          <div>
559            <div>
560              <h3 class="title"><a id="id1652629"></a>Utility Changes:</h3>
561            </div>
562          </div>
563        </div>
564        <div class="orderedlist">
565          <ol type="1">
566            <li>Fix a bug that caused db_verify to not check the order on leaf pages
567	which were the leftmost children of an internal node. [#13004]</li>
568            <li>Fix a bug that caused db_hotbackup to not backup queue extent files.
569	[#13848]</li>
570            <li>Fix a bug so that db_verify no longer reports that an unused hash
571	page is not fully zeroed. [#14030]</li>
572            <li>Fix a bug where db_stat ignored the -f option to return "fast
573	statistics". [#14283]</li>
574            <li>Fix a bug that prevented the db_stat utility from opening database
575files with write permission so that meta data statistics would be
576updated. [#14755]</li>
577            <li>Fix a bug in db_hotbackup related to windows. Sub-directories are
578	now ignored. [#14757]</li>
579          </ol>
580        </div>
581      </div>
582      <div class="sect2" lang="en" xml:lang="en">
583        <div class="titlepage">
584          <div>
585            <div>
586              <h3 class="title"><a id="id1652610"></a>Configuration, Documentation, Portability and Build Changes:</h3>
587            </div>
588          </div>
589        </div>
590        <div class="orderedlist">
591          <ol type="1">
592            <li>The Berkeley DB 4.3 and 4.4 releases disallowed using the
593--with-uniquename configuration option with the C++, Java, or RPC
594--enable-XXX options. The 4.5 release returns to the 4.2 release
595behavior, allowing those combinations of configuration options. [#14067]</li>
596            <li>Fix build issues when CONFIG_TEST is not enabled for Tcl. [#14507]</li>
597            <li>There are updated build instructions for Berkeley DB PHP module on
598	Linux. [#14249]</li>
599            <li>Use libtool's "standard" environment variable names so that you can
600set "AR" to "ar -X64" for example, and modify both libtool and the
601Makefile commands. Remove the install-strip target from the Makefile,
602it is no longer used. [#14726]</li>
603            <li>Fix a bug where, when a database is opened with the DB_THREAD flag
604(the default in Java), and an operation in one thread causes the
605database to be truncated (typically when the last page in the database
606is freed) concurrently with a read or write in another thread, there can
607be arbitrary data loss, as Windows zeros out pages from the read/write
608location to the end of the file. [#15063]</li>
609          </ol>
610        </div>
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