Documentation Source Text

proc chng {date desc {options {}}} {
  global nChng aChng
  set aChng($nChng) [list $date $desc $options]
  incr nChng
}

chng {2016-04-00 (3.12.0)} {
<p><b>Potentially Disruptive Change:</b>
<li>The [SQLITE_DEFAULT_PAGE_SIZE] is increased from 1024 to 4096.  
    The [SQLITE_DEFAULT_CACHE_SIZE] is changed from 2000 to -2000 so 
    the same amount of cache memory is used by default.
    See the application note on the
    [version 3.12.0 page size change] for further information.
<p><b>Performance enhancements:</b>
<li>Enhancements to the [https://www.sqlite.org/src/doc/trunk/doc/lemon.html|Lemon]
    parser generator so that it creates a smaller and faster SQL parser.
<li>Only create [master journal] files if two or more attached databases are all
    modified, do not have [PRAGMA synchronous] set to OFF, and
    do not have the [journal_mode] set to OFF, MEMORY, or WAL.
<li>Only create [statement journal] files when their size exceeds a threshold.
    Otherwise the journal is held in memory and no I/O occurs.  The threshold
    can be configured at compile-time using [SQLITE_STMTJRNL_SPILL] or at
    start-time using [sqlite3_config]([SQLITE_CONFIG_STMTJRNL_SPILL]).
<li>The query planner is able to optimize IN operators on [virtual tables]
    even if the [xBestIndex] method does not set the
    sqlite3_index_constraint_usage.omit flag of the
    virtual table column to the left of the IN operator.
<li>The query planner now does a better job of optimizing [virtual table]
    accesses in a 3-way or higher join where constraints on the virtual
    table are split across two or more other tables of the join.
<li>More efficient handling of [application-defined SQL functions], especially
    in cases where the application defines hundreds or thousands of 
    custom functions.
<li>The query planner considers the LIMIT clause when estimating the cost
    or ORDER BY.
<li>The configure script (on unix) automatically detects the availablity of
    pread() and pwrite() and sets of compile-time options to use those OS
    interfaces if they are available.
<li>Reduce the amount of memory needed to hold the schema.
<li>Other miscellanous micro-optimizations for improved performance and reduced
    memory usage.
<p><b>New Features:</b>
<li>Added the [SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER] option to [sqlite3_db_config()]
    which allows the two-argument version of the [fts3_tokenizer()] SQL function to
    be enabled or disabled at run-time.
<li>Added the [https://www.sqlite.org/src/artifact/d7cc99350?ln=403-443|sqlite3rbu_bp_progress()]
    interface to the [RBU] extension.
<li>The [PRAGMA defer_foreign_keys=ON] statement now also disables 
    [foreign key actions|RESTRICT actions] on foreign key.
<li>Added the [SQLITE_DEFAULT_SYNCHRONOUS] and [SQLITE_DEFAULT_WAL_SYNCHRONOUS]
    compile-time options.  The [SQLITE_DEFAULT_SYNCHRONOUS] compile-time option
    replaces the [SQLITE_EXTRA_DURABLE] option, which is no longer supported.
<li>Enhanced the ".stats" command in the [command-line shell] to show more
    information about I/O performance obtained from /proc, when available.
<p><b>Bug fixes:</b>
<li>Make sure the [sqlite3_set_auxdata()] values from multiple triggers
    within a single statement do not interfere with one another.
    Ticket [https://www.sqlite.org/src/info/dc9b1c91|dc9b1c91].
<li>Fix the code generator for expressions of the form "x IN (SELECT...)" where
    the SELECT statement on the RHS is a correlated subquery.
    Ticket [https://www.sqlite.org/src/info/5e3c886796e5512e|5e3c886796e5512e].
<li>Fix a harmless TSAN warning associated with the [sqlite3_db_readonly()] interface.
}

chng {2016-03-03 (3.11.1)} {
<li>Improvements to the Makefiles and build scripts used by VisualStudio.
<li>Fix an [FTS5] issue in which the 'optimize' command could cause index corruption.
<li>Fix a buffer overread that might occur if [FTS5] is used to query a corrupt
    database file.