harningt / sqlite3_release_news

<blockquote> SQLite <a href="http://sqlite.org/releaselog/3_7_11.html">version 3.7.11</a> is a regularly scheduled maintenance release which was rushed out early due to a <a href="http://www.sqlite.org/src/info/b7c8682cc1">bug in the query optimizer</a> introduced in the previous release. The bug is obscure - it changes a LEFT JOIN into an INNER JOIN in some cases when there is a 3-way join and OR terms in the WHERE clause. But it was considered serious enough to rush out a fix. Apart from this one problem, SQLite <a href="http://sqlite.org/releaselog/3_7_10.html">version 3.7.10</a> has not given any trouble. Upgrading to <a href="http://sqlite.org/releaselog/3_7_11.html">version 3.7.11</a> from versions 3.7.6.3, 3.7.7, 3.7.7.1, 3.7.8, or 3.7.9 is optional. Upgrading from other releases, including the previous release 3.7.10, is recommended. <p> Other enhancements found in this release are enumerated in the <a href="http://sqlite.org/releaselog/3_7_11.html">change log</a>. </p></blockquote>

2012-03-20T00:00:00

2012_march_20

2012-March-20 - <a href="http://sqlite.org/releaselog/3_7_11.html">Version 3.7.11</a>

http://sqlite.org/news.html

<blockquote> SQLite <a href="http://sqlite.org/releaselog/3_7_10.html">version 3.7.10</a> is a regularly scheduled maintenance release. Upgrading from version 3.7.6.3, 3.7.7, 3.7.7.1, 3.7.8, or 3.7.9 is optional. Upgrading from other releases is recommended. <p> The <a href="http://sqlite.org/c3ref/c_config_covering_index_scan.html#sqliteconfigpcache">SQLITE_CONFIG_PCACHE</a> mechanism has been replaced with <a href="http://sqlite.org/c3ref/c_config_covering_index_scan.html#sqliteconfigpcache2">SQLITE_CONFIG_PCACHE2</a>. If you do not know what this mechanism is (it is an extreme corner-case and is seldom used) then this change will not effect you in the least.</p> <p> The default <a href="http://sqlite.org/fileformat2.html#schemaformat">schema format number</a> for new database files has changed from 1 to 4. SQLite has been able to generate and read database files using schema format 4 for six years. But up unto now, the default schema format has been 1 so that older versions of SQLite could read and write databases generated by newer versions of SQLite. But those older versions of SQLite have become so scarce now that it seems reasonable to make the new format the default.</p> <p> SQLite is changing some of the assumptions it makes above the behavior of disk drives and flash memory devices during a sudden power loss. This change is completely transparent to applications. Read about the <a href="http://sqlite.org/psow.html">powersafe overwrite</a> property for additional information.</p> <p> Lots of new interfaces have been added in this release: </p><ul><li> <a href="http://sqlite.org/c3ref/db_release_memory.html">sqlite3_db_release_memory()</a> </li><li> <a href="http://sqlite.org/pragma.html#pragma_shrink_memory">PRAGMA shrink_memory</a> </li><li> <a href="http://sqlite.org/c3ref/db_filename.html">sqlite3_db_filename()</a> </li><li> <a href="http://sqlite.org/c3ref/stmt_busy.html">sqlite3_stmt_busy()</a> </li><li> <a href="http://sqlite.org/c3ref/uri_boolean.html">sqlite3_uri_boolean()</a> </li><li> <a href="http://sqlite.org/c3ref/uri_boolean.html">sqlite3_uri_int64()</a> </li></ul><p> The <a href="http://sqlite.org/pragma.html#pragma_cache_size">PRAGMA cache_size</a> statement has been enhanced. Formerly, you would use this statement to tell SQLite how many pages of the database files it should hold in its cache at once. The total memory requirement would depend on the database page size. Now, if you give <a href="http://sqlite.org/pragma.html#pragma_cache_size">PRAGMA cache_size</a> a negative value -N, it will allocate roughly N <a href="http://en.wikipedia.org/wiki/Kibibyte">kibibytes</a> of memory to cache, divided up according to page size. This enhancement allows programs to more easily control their memory usage.</p> <p> There have been several obscure bug fixes. One noteworthy bug, ticket <a href="http://www.sqlite.org/src/info/ff5be73dee">ff5be73dee</a>, could in theory result in a corrupt database file if a power loss occurred at just the wrong moment on an unusually cantankerous disk drive. But that is mostly a theoretical concern and is very unlikely to happen in practice. The bug was found during laboratory testing and has never been observed to occur in the wild. </p></blockquote>

2012-01-16T00:00:00

2012_january_16

2012-January-16 - <a href="http://sqlite.org/releaselog/3_7_10.html">Version 3.7.10</a>

http://sqlite.org/news.html

<blockquote> SQLite <a href="http://sqlite.org/releaselog/3_7_9.html">version 3.7.9</a> is a regularly scheduled maintenance release. Upgrading from version 3.7.6.3, 3.7.7, 3.7.7.1, and 3.7.8 is optional. Upgrading from other versions is recommended. <p> The <a href="http://sqlite.org/compile.html#enable_stat2">SQLITE_ENABLE_STAT2</a> compile-time option is now a no-op. The enhanced query-planner functionality formerly available using SQLITE_ENABLE_STAT2 is now available through <a href="http://sqlite.org/compile.html#enable_stat3">SQLITE_ENABLE_STAT3</a>. The enhanced query planning is still disabled by default. However, future releases of SQLite might convert STAT3 from an enable-option to a disable-option so that it is available by default and is only omitted upon request.</p> <p> The <a href="http://sqlite.org/fts3.html#fts4">FTS4</a> full-text search engine has been enhanced such that tokens in the search string that begin with "^" must be the first token in their respective columns in order to match. Formerly, "^" characters in the search string were simply ignored. Hence, if a legacy application was including "^" characters in FTS4 search strings, thinking that they would always be ignored, then those legacy applications might break with this update. The fix is simply remove the "^" characters from the search string.</p> <p> See the <a href="http://sqlite.org/releaselog/3_7_9.html">change summary</a> for additional changes associated with this release. </p></blockquote>

2011-11-01T00:00:00

2011_november_01

2011-November-01 - <a href="http://sqlite.org/releaselog/3_7_9.html">Version 3.7.9</a>

http://sqlite.org/news.html

<blockquote> SQLite <a href="http://sqlite.org/releaselog/3_7_8.html">version 3.7.8</a> is a quarterly maintenance release. Upgrading from versions 3.7.6.3, 3.7.7, or 3.7.7.1 is optional. Upgrading from other versions is recommended. <p> This release features a new "external merge sort" algorithm used to implement ORDER BY and GROUP BY and also to presort the content of an index for CREATE INDEX. The new algorithm does approximately the same number of comparisons and I/Os as before, but the I/Os are much more sequential and so runtimes are greatly reduced when the size of the set being sorted is larger than the filesystem cache. The performance improvement can be dramatic - orders of magnitude faster for large CREATE INDEX commands. On the other hand, the code is slightly slower (1% or 2%) for a small CREATE INDEX. Since CREATE INDEX is not an operation that commonly occurs on a speed-critical path, we feel that this tradeoff is a good one. The slight slowdown for small CREATE INDEX statements might be recovered in a future release. ORDER BY and GROUP BY operations should now be faster for all cases, large and small.</p> <p> The query planner has been enhanced to do a better job of handling the DISTINCT keyword on SELECT statements.</p> <p> There has been a lot of work on the default <a href="http://sqlite.org/vfs.html">VFSes</a>. The unix VFS has been enhanced to include more overrideable system calls - a feature requested by Chromium to make it easier to build SQLite into a sandbox. The windows VFS has been enhanced to be more resistant to interference from anti-virus software.</p> <p> Every version of SQLite is better tested than the previous, and 3.7.8 is no exception to this rule. Version 3.7.8 has been used internally by the SQLite team for mission critical functions and has performed flawlessly. And, of course, it passes our rigorous <a href="http://sqlite.org/testing.html">testing</a> procedures with no problems detected. Version 3.7.8 is recommended for all new development. </p></blockquote>

2011-09-19T00:00:00

2011_september_19

2011-September-19 - <a href="http://sqlite.org/releaselog/3_7_8.html">Version 3.7.8</a>

http://sqlite.org/news.html

<blockquote> SQLite <a href="http://sqlite.org/releaselog/3_7_16.html">version 3.7.16</a> is a regularly scheduled release of SQLite. This release contains several langauge enhancements and improvements to the query optimizer. A list of the major enhancements and optimizations can be see on the <a href="http://sqlite.org/releaselog/3_7_16.html">change log</a>. <p> There was one important bug fix (see <a href="http://www.sqlite.org/src/info/fc7bd6358f">Ticket fc7bd6358f</a>) that addresses an incorrect query result that could have occurred in a three-way join where the join constraints compared INTEGER columns to TEXT columns. This issue had been in the code for time out of mind and had never before been reported, so we surmise that it is very obscure. Nevertheless, all users are advised to upgrade to avoid any future problems associated with this issue. </p></blockquote>

2013-03-18T00:00:00

2013_mar_18

2013-Mar-18 - Release 3.7.16

http://sqlite.org/news.html

<blockquote> SQLite <a href="http://sqlite.org/releaselog/3_7_15_2.html">version 3.7.15.2</a> is a patch release that fixes a single bug that was introduced in version <a href="http://sqlite.org/releaselog/3_7_15.html">version 3.7.15</a>. The fix is a 4-character edit to a single line of code. Other than this 4-character change and the update of the version number, nothing has changed from <a href="http://sqlite.org/releaselog/3_7_15_1.html">version 3.7.15.1</a>. </blockquote>

2013-01-09T00:00:00

2013_jan_09

2013-Jan-09 - Release 3.7.15.2

http://sqlite.org/news.html

<blockquote> SQLite <a href="http://sqlite.org/releaselog/3_7_15_1.html">version 3.7.15.1</a> is a patch release that fixes a single bug that was introduced in version <a href="http://sqlite.org/releaselog/3_7_15.html">version 3.7.15</a>. The fix involved changing two lines of code and adding a single assert(). This release also includes some new test cases to prevent a regression of the bug, and the version number is increased, of course. But otherwise, nothing has changed from <a href="http://sqlite.org/releaselog/3_7_15.html">version 3.7.15</a>. </blockquote>

2012-12-19T00:00:00

2012_dec_19

2012-Dec-19 - Release 3.7.15.1

http://sqlite.org/news.html

<blockquote> SQLite <a href="http://sqlite.org/releaselog/3_7_15.html">version 3.7.15</a> is a regularly schedule release of SQLite. This release contains several improvements to the query planner and optimizer and one important bug fix. This is the first release to officially support Windows 8 Phone. <p> The important bug fix is a problem that can lead to segfaults when using <a href="http://sqlite.org/sharedcache.html">shared cache mode</a> on a schema that contains a <a href="http://sqlite.org/lang_expr.html#collateop">COLLATE operator</a> within a <a href="http://sqlite.org/lang_createtable.html#ckconst">CHECK constraint</a> or within a <a href="http://sqlite.org/lang_createview.html">view</a>. Collating functions are associated with individual database connections. But a pointer to the collating function was also being cached within expressions. If an expression was part of the schema and contained a cached collating function, it would point to the collating function in the database connection that originally parsed the schema. If that database connection closed while other database connections using the same shared cache continued to operate, they other database connections would try to use the deallocated collating function in the database connection that closed. The fix in version 3.7.15 was to not cache collating function pointers in the expression structure but instead look them up each time a new statement is prepared.</p> <p> This release also contains some important enhancements to the query planner which should (we hope) make some queries run faster. The enhancements include:</p> <p> </p><ol><li><p>When doing a full-table scan, try to use an index instead of the original table, under the theory that indices contain less information and are thus smaller and hence require less disk I/O to scan.</p> <p> </p></li><li><p>Enhance the <a href="http://sqlite.org/lang_expr.html#in_op">IN operator</a> to allow it to make use of indices that have <a href="http://sqlite.org/datatype3.html#affinity">numeric affinity</a>.</p> <p> </p></li><li><p>Do a better job of recognizing when an ORDER BY clause can be implemented using indices - especially in cases where the ORDER BY clause contains terms from two or more tables in a join.</p> </li></ol></blockquote>

2012-12-12T00:00:00

2012_dec_12

2012-Dec-12 - Release 3.7.15

http://sqlite.org/news.html

<blockquote> SQLite <a href="http://sqlite.org/releaselog/3_7_14_1.html">version 3.7.14.1</a> is a patch release. Changes from the baseline version 3.7.14 are minimal and are restricted to fixing three bugs. <p> One of the fixed bugs is a long-standing issue with the TCL interface. Another is an external compiler bug that SQLite merely works around and that only comes up if you are using the VisualStudio-2012 compiler to generate WinRT applications on ARM with optimizations enabled. The third problem is an SQLite core bug, introduced in version 3.7.14, that can cause a segfault if a query contains a LEFT JOIN that contains an OR in the ON clause. </p></blockquote>

2012-10-04T00:00:00

2012_oct_04

2012-Oct-04 - Release 3.7.14.1

http://sqlite.org/news.html

<blockquote> SQLite <a href="http://sqlite.org/releaselog/3_7_14.html">version 3.7.14</a> is a regularly scheduled maintenance release of SQLite. The previous release continues to work well. Upgrading is optional. <p> Version 3.7.14 drops native support for OS/2. We are not aware of any active projects that were using SQLite on OS/2 and since the SQLite developers had no way of testing on OS/2 it seemed like it was time to simply remove the OS/2 code from the SQLite tree. If there are OS/2 projects out there that still need SQLite support, they can continue to maintain their own private <a href="http://sqlite.org/vfs.html">VFS</a> which can be linked to SQLite at start-time using the <a href="http://sqlite.org/c3ref/vfs_find.html">sqlite3_vfs_register()</a> interface.</p> <p> The <a href="http://sqlite.org/c3ref/close.html">sqlite3_close_v2()</a> interface has been added. The sqlite3_close_v2() interface differs from sqlite3_close() in that it is designed to work better for host language that use a garbage collector. With the older sqlite3_close() interface, the associated <a href="http://sqlite.org/c3ref/stmt.html">prepared statements</a> and <a href="http://sqlite.org/c3ref/backup.html">sqlite3_backup</a> objects must be destroyed before the database connection. With the newer sqlite3_close_v2() interface, the objects can be destroyed in any order.</p> <p> This release also includes performance improvements to the sort algorithm that is used to implement ORDER BY and CREATE INDEX. And the query planner has been enhanced to better use covering indices on queries that use OR terms in the WHERE clause. </p></blockquote>

2012-09-03T00:00:00

2012_sep_03

2012-Sep-03 - Release 3.7.14

http://sqlite.org/news.html