 
Small. Fast. Reliable.
Choose any three.
 
SQLite Release 3.12.1 On 2016-04-08
- Fix a boundary condition error introduced by version 3.12.0
    that can result in a crash during heavy SAVEPOINT usage.
    Ticket 7f7f8026eda38.
- Fix views so that they inherit column datatypes from the 
    table that they are defined against, when possible.
- Fix the query planner so that IS and IS NULL operators are able
    to drive an index on a LEFT OUTER JOIN.
Hashes:
 
- SQLITE_SOURCE_ID: "2016-04-08 15:09:49 fe7d3b75fe1bde41511b323925af8ae1b910bc4d"
- SHA1 for sqlite3.c: ebb18593350779850e3e1a930eb84a70fca8c1d1
Changes carried forward from version 3.12.0 (2016-03-29):
Potentially Disruptive Change:
- 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.
Performance enhancements:
 
- Enhancements to the Lemon parser generator
    so that it creates a smaller and faster SQL parser.
- 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.
- 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).
- 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.
- 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.
- More efficient handling of application-defined SQL functions, especially
    in cases where the application defines hundreds or thousands of 
    custom functions.
- The query planner considers the LIMIT clause when estimating the cost
    of ORDER BY.
- The configure script (on unix) automatically detects
    pread() and pwrite() and sets compile-time options to use those OS
    interfaces if they are available.
- Reduce the amount of memory needed to hold the schema.
- Other miscellaneous micro-optimizations for improved performance and reduced
    memory usage.
New Features:
 
- 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.
- Added the sqlite3rbu_bp_progress()
    interface to the RBU extension.
- The PRAGMA defer_foreign_keys=ON statement now also disables 
    RESTRICT actions on foreign key.
- Added the sqlite3_system_errno() interface.
- 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.
- Enhanced the ".stats" command in the command-line shell to show more
    information about I/O performance obtained from /proc, when available.
Bug fixes:
 
- Make sure the sqlite3_set_auxdata() values from multiple triggers
    within a single statement do not interfere with one another.
    Ticket dc9b1c91.
- Fix the code generator for expressions of the form "x IN (SELECT...)" where
    the SELECT statement on the RHS is a correlated subquery.
    Ticket 5e3c886796e5512e.
- Fix a harmless TSAN warning associated with the sqlite3_db_readonly() interface.
A complete list of SQLite releases
      in a single page and a chronology are both also available.  
      A detailed history of every
      check-in is available at
      
      SQLite version control site.