SQLite v3.16.2

Fix the REPLACE statement for WITHOUT ROWID tables that lack secondary indexes so that it works correctly with triggers and foreign keys. This was a new bug caused by performance optimizations added in version 3.16.0. Ticket 30027b613b4
Fix the sqlite3_value_text() interface so that it correctly translates content generated by zeroblob() into a string of all 0x00 characters. This is a long-standing issue discovered after the 3.16.1 release by OSS-Fuzz
Fix the bytecode generator to deal with a subquery in the FROM clause that is itself a UNION ALL where one side of the UNION ALL is a view that contains an ORDER BY. This is a long-standing issue that was discovered after the release of 3.16.1. See ticket 190c2507.
Adjust the sqlite3_column_count() API so it more often returns the same values for PRAGMA statements as it did in prior releases, to minimize disruption to applications that might be using that interface in unexpected ways.

Uses 9% fewer CPU cycles. (See the CPU performance measurement report for details on how the this performance increase was computed.)
Added experimental support for PRAGMA functions.
Added the SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE option to sqlite3_db_config().
Enhance the date and time functions so that the 'unixepoch' modifier works for the full span of supported dates.
Changed the default configuration of the lookaside memory allocator from 500 slots of 128 bytes each into 125 slots of 512 bytes each.
Enhanced "WHERE x NOT NULL" partial indexes so that they are usable if the "x" column appears in a LIKE or GLOB operator.
Enhanced sqlite3_interrupt() so that it interrupts checkpoint operations that are in process.
Enhanced the LIKE and GLOB matching algorithm to be faster for cases when the pattern contains multiple wildcards.
Added the SQLITE_FCNTL_WIN32_GET_HANDLE file control opcode.
Added ".mode quote" to the command-line shell.
Added ".lint fkey-indexes" to the command-line shell.
Added the .imposter dot-command to the command-line shell.
Added the remember(V,PTR) SQL function as a loadable extension.
Rename the SQLITE_OMIT_BUILTIN_TEST compile-time option to SQLITE_UNTESTABLE to better reflect the implications of using it.
Bug Fixes:

Fix a long-standing bug in the query planner that caused incorrect results on a LEFT JOIN where the left-hand table is a subquery and the join constraint is a bare column name coming from the left-hand subquery. Ticket 2df0107b.
Correctly handle the integer literal -0x8000000000000000 in the query planner.
Hashes:

SQLITE_SOURCE_ID: "2017-01-02 11:57:58 04ac0b75b1716541b2b97704f4809cb7ef19cccf"
SHA1 for sqlite3.c: e2920fb885569d14197c9b7958e6f1db573ee669

Multiple bug fixes to the row value logic that was introduced in version 3.15.0.
Fix a NULL pointer dereference in ATTACH/DETACH following a maliciously constructed syntax error. Ticket 2f1b168ab4d4844.
Fix a crash that can occur following an out-of-memory condition in the built-in instr() function.
In the JSON extension, fix the JSON validator so that it correctly rejects invalid backslash escapes within strings.

Added support for row values.
Allow deterministic SQL functions in the WHERE clause of a partial index.
Added the "modeof=filename" URI parameter on the unix VFS
Added support for SQLITE_DBCONFIG_MAINDBNAME.
Added the ability to VACUUM an ATTACH-ed database.
Enhancements to the command-line shell:
Add the ".testcase" and ".check" dot-commands.
Added the --new option to the ".open" dot-command, causing any prior content in the database to be purged prior to opening.
Enhance the fts5vocab virtual table to handle "ORDER BY term" efficiently.
Miscellaneous micro-optimizations reduce CPU usage by more than 7% on common workloads. Most optimization in this release has been on the front-end (sqlite3_prepare_v2()).
Bug Fixes:
The multiply operator now correctly detects 64-bit integer overflow and promotes to floating point in all corner-cases. Fix for ticket 1ec41379c9c1e400.
Correct handling of columns with redundant unique indexes when those columns are used on the LHS of an IN operator. Fix for ticket 0eab1ac759.
Skip NULL entries on range queries in indexes on expressions. Fix for ticket 4baa46491212947.
Ensure that the AUTOINCREMENT counters in the sqlite_sequence table are initialized doing "Xfer Optimization" on "INSERT ... SELECT" statements. Fix for ticket 7b3328086a5c116c.
Make sure the ORDER BY LIMIT optimization (from check-in 559733b09e) works with IN operators on INTEGER PRIMARY KEYs. Fix for ticket 96c1454c
Hashes:
SQLITE_SOURCE_ID: "2016-10-14 1030 707875582fcba352b4906a595ad89198d84711d8"
SHA1 for sqlite3.c: fba106f8f6493c66eeed08a2dfff0907de54ae76

Improved support for using the STDCALL calling convention in winsqlite3.dll.
Fix the sqlite3_trace_v2() interface so that it is disabled if either the callback or the mask arguments are zero, in accordance with the documentation.
Fix commenting errors and improve the comments generated on EXPLAIN listings when the -DSQLITE_ENABLE_EXPLAIN_COMMENTS compile-time option is used.
Fix the ".read" command in the command-line shell so that it understands that its input is not interactive.
Correct affinity computations for a SELECT on the RHS of an IN operator. Fix for ticket 199df4168c.
The ORDER BY LIMIT optimization is not valid unless the inner-most IN operator loop is actually used by the query plan. Fix for ticket 0c4df46116e90f92.
Fix an internal code generator problem that was causing some DELETE operations to no-op. Ticket ef360601

Fix to the --rbu option of sqldiff.

Postpone I/O associated with TEMP files for as long as possible, with the hope that the I/O can ultimately be avoided completely.
Merged the session extension into trunk.
Added the ".auth ON|OFF" command to the command-line shell.
Added the "--indent" option to the ".schema" and ".fullschema" commands of the command-line shell, to turn on pretty-printing.
Added the ".eqp full" option to the command-line shell, that does both EXPLAIN and EXPLAIN QUERY PLAN on each statement that is evaluated.
Improved unicode filename handling in the command-line shell on Windows.
Improved resistance against goofy query planner decisions caused by incomplete or incorrect modifications to the sqlite_stat1 table by the application.
Added the sqlite3_db_config(db,SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION) interface which allows the sqlite3_load_extension() C-API to be enabled while keeping the load_extension() SQL function disabled for security.
Change the temporary directory search algorithm on Unix to allow directories with write and execute permission, but without read permission, to serve as temporary directories. Apply this same standard to the "." fallback directory.
Bug Fixes:
Fix a problem with the multi-row one-pass DELETE optimization that was causing it to compute incorrect answers with a self-referential subquery in the WHERE clause. Fix for ticket dc6ebeda9396087
Fix a possible segfault with DELETE when table is a rowid table with an INTEGER PRIMARY KEY and the WHERE clause contains a OR and the table has one or more indexes that are able to trigger the OR optimization, but none of the indexes reference any table columns other than the INTEGER PRIMARY KEY. Ticket 16c9801ceba49.
When checking for the WHERE-clause push-down optimization, verify that all terms of the compound inner SELECT are non-aggregate, not just the last term. Fix for ticket f7f8c97e97597.
Fix a locking race condition in Windows that can occur when two or more processes attempt to recover the same hot journal at the same time.

Fix a backwards compatibility problem in version 3.12.0 and 3.12.1: Columns declared as "INTEGER" PRIMARY KEY (with quotes around the datatype keyword) where not being recognized as an INTEGER PRIMARY KEY, which resulted in an incompatible database file. Ticket 7d7525cb01b68
Fix a bug (present since version 3.9.0) that can cause the DELETE operation to miss rows if PRAGMA reverse_unordered_selects is turned on. Ticket a306e56ff68b8fa5
Fix a bug in the code generator that can causes incorrect results if two or more virtual tables are joined and the virtual table used in outer loop of the join has an IN operator constraint.
Correctly interpret negative "PRAGMA cache_size" values when determining the cache size used for sorting large amounts of data.

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.

Improvements to the Makefiles and build scripts used by VisualStudio.
Fix an FTS5 issue in which the 'optimize' command could cause index corruption.
Fix a buffer overread that might occur if FTS5 is used to query a corrupt database file.
Increase the maximum "scope" value for the spellfix1 extension from 6 to 30.

General improvements:
Enhanced WAL mode so that it works efficiently with transactions that are larger than the cache_size.
Added the FTS5 detail option.
Added the "EXTRA" option to PRAGMA synchronous that does a sync of the containing directory when a rollback journal is unlinked in DELETE mode, for better durability. The SQLITE_EXTRA_DURABLE compile-time option enables PRAGMA synchronous=EXTRA by default.
Enhanced the query planner so that it is able to use a covering index as part of the OR optimization.
Avoid recomputing NOT NULL and CHECK constraints on unchanged columns in UPDATE statement.
Many micro-optimizations, resulting in a library that is faster than the previous release.
Enhancements to the command-line shell:
By default, the shell is now in "auto-explain" mode. The output of EXPLAIN commands is automatically formatted.
Added the ".vfslist" dot-command.
The SQLITE_ENABLE_EXPLAIN_COMMENTS compile-time option is now turned on by default in the standard builds.
Enhancements to the TCL Interface:
If a database connection is opened with the "-uri 1" option, then URI filenames are honored by the "backup" and "restore" commands.
Added the "-sourceid" option to the "sqlite3" command.
Makefile improvements:
Improved pthreads detection in configure scripts.
Add the ability to do MSVC Windows builds from the amalgamation tarball.
Bug fixes:
Fix an issue with incorrect sharing of VDBE temporary registers between co-routines that could cause incorrect query results in obscure cases. Ticket d06a25c84454a.
Fix a problem in the sqlite3_result_subtype() interface that could cause problems for the json1 extension under obscure circumstances. Fix for ticket f45ac567eaa9f9.
Escape control characters in JSON strings. Fix for ticket ad2559db380abf8.
Reenable the xCurrentTime and xGetLastError methods in the built-in unix VFSes as long as SQLITE_OMIT_DEPRECATED is not defined.
Backwards Compatibility:
Because of continuing security concerns, the two-argument version of of the seldom-used and little-known fts3_tokenizer() function is disabled unless SQLite is compiled with the SQLITE_ENABLE_FTS3_TOKENIZER.

Critical bug fix:

Version 3.10.0 introduced a case-folding bug in the LIKE operator which is fixed by this patch release. Ticket 80369eddd5c94.
Other miscellaneous bug fixes:

Fix a use-after-free that can occur when SQLite is compiled with -DSQLITE_HAS_CODEC.
Fix the build so that it works with -DSQLITE_OMIT_WAL.
Fix the configure script for the amalgamation so that the --readline option works again on Raspberry PIs.

New feature:
Add the SQLITE_FCNTL_JOURNAL_POINTER file control.
Bug fix:
Fix a 16-month-old bug in the query planner that could generate incorrect results when a scalar subquery attempts to use the block sorting optimization. Ticket cb3aa0641d9a4.

General improvements:

Added support for LIKE, GLOB, and REGEXP operators on virtual tables.
Added the colUsed field to sqlite3_index_info for use by the sqlite3_module.xBestIndex method.
Enhance the PRAGMA cache_spill statement to accept a 32-bit integer parameter which is the threshold below which cache spilling is prohibited.
On unix, if a symlink to a database file is opened, then the corresponding journal files are based on the actual filename, not the symlink name.
Added the "--transaction" option to sqldiff.
Added the sqlite3_db_cacheflush() interface.
Added the sqlite3_strlike() interface.
When using memory-mapped I/O map the database file read-only so that stray pointers and/or array overruns in the application cannot accidently modify the database file.
Added the experimental sqlite3_snapshot_get(), sqlite3_snapshot_open(), and sqlite3_snapshot_free() interfaces. These are subject to change or removal in a subsequent release.
Enhance the 'utc' modifier in the date and time functions so that it is a no-op if the date/time is known to already be in UTC. (This is not a compatibility break since the behavior has long been documented as "undefined" in that case.)
Added the json_group_array() and json_group_object() SQL functions in the json extension.
Added the SQLITE_LIKE_DOESNT_MATCH_BLOBS compile-time option.
Many small performance optimizations.
Portability enhancements:

Work around a sign-exension bug in the optimizer of the HP C compiler on HP/UX. (details)
Enhancements to the command-line shell:

Added the ".changes ON|OFF" and ".vfsinfo" dot-commands.
Translate between MBCS and UTF8 when running in cmd.exe on Windows.
Enhancements to makefiles:

Added the --enable-editline and --enable-static-shell options to the various autoconf-generated configure scripts.
Omit all use of "awk" in the makefiles, to make building easier for MSVC users.
Important fixes:

Fix inconsistent integer to floating-point comparison operations that could result in a corrupt index if the index is created on a table column that contains both large integers and floating point values of similar magnitude. Ticket 38a97a87a6.
Fix an infinite-loop in the query planner that could occur on malformed common table expressions.
Various bug fixes in the sqldiff tool.

Fix the json1 extension so that it does not recognize ASCII form-feed as a whitespace character, in order to comply with RFC-7159. Fix for ticket 57eec374ae1d0a1d
Add a few #ifdef and build script changes to address compilation issues that appeared after the 3.9.0 release.
SQLITE_SOURCE_ID: ""2015-10-16 17:31:12 767c1727fec4ce11b83f25b3f1bfcfe68a2c8b02"
SHA1 for sqlite3.c: 5e6d1873a32d82c2cf8581f143649940cac8ae49

Restore an undocumented side-effect of PRAGMA cache_size: force the database schema to be parsed if the database has not been previously accessed.
Fix a long-standing problem in sqlite3_changes() for WITHOUT ROWID tables that was reported a few hours after the 3.8.11 release.

Added the experimental RBU extension. Note that this extension is experimental and subject to change in incompatible ways.
Added the experimental FTS5 extension. Note that this extension is experimental and subject to change in incompatible ways.
Added the sqlite3_value_dup() and sqlite3_value_free() interfaces.
Enhance the spellfix1 extension to support ON CONFLICT clauses.
The IS operator is now able to drive indexes.
Enhance the query planner to permit automatic indexing on FROM-clause subqueries that are implemented by co-routine.
Disallow the use of "rowid" in common table expressions.
Added the PRAGMA cell_size_check command for better and earlier detection of database file corruption.
Added the matchinfo 'b' flag to the matchinfo() function in FTS3.
Improved fuzz-testing of database files, with fixes for problems found.
Add the fuzzcheck test program and automatically run this program using both SQL and database test cases on "make test".
Added the SQLITE_MUTEX_STATIC_VFS1 static mutex and use it in the Windows VFS.
The sqlite3_profile() callback is invoked (by sqlite3_reset() or sqlite3_finalize()) for statements that did not run to completion.
Enhance the page cache so that it can preallocate a block of memory to use for the initial set page cache lines. Set the default preallocation to 100 pages. Yields about a 5% performance increase on common workloads.
Miscellaneous micro-optimizations result in 22.3% more work for the same number of CPU cycles relative to the previous release. SQLite now runs twice as fast as version 3.8.0 and three times as fast as version 3.3.9. (Measured using cachegrind on the speedtest1.c workload on Ubuntu 14.04 x64 with gcc 4.8.2 and -Os. Your performance may vary.)
Added the sqlite3_result_zeroblob64() and sqlite3_bind_zeroblob64() interfaces.
Important bug fixes:

Fix CREATE TABLE AS so that columns of type TEXT never end up holding an INT value. Ticket f2ad7de056ab1dc9200
Fix CREATE TABLE AS so that it does not leave NULL entries in the sqlite_master table if the SELECT statement on the right-hand side aborts with an error. Ticket 873cae2b6e25b
Fix the skip-scan optimization so that it works correctly when the OR optimization is used on WITHOUT ROWID tables. Ticket 8fd39115d8f46
Fix the sqlite3_memory_used() and sqlite3_memory_highwater() interfaces so that they actually do provide a 64-bit answer.

Fix an index corruption issue introduced by version 3.8.7. An index with a TEXT key can be corrupted by an INSERT into the corresponding table if the table has two nested triggers that convert the key value to INTEGER and back to TEXT again. Ticket 34cd55d68e0
SQLITE_SOURCE_ID: "2015-05-20 18:17:19 2ef4f3a5b1d1d0c4338f8243d40a2452cc1f7fe4"
SHA1 for sqlite3.c: 638abb77965332c956dbbd2c8e4248e84da4eb63

Make sqlite3_compileoption_used() responsive to the SQLITE_ENABLE_DBSTAT_VTAB compile-time option.
Fix a harmless warning in the command-line shell on some versions of MSVC.
Fix minor issues with the dbstat virtual table.
SQLITE_SOURCE_ID: "2015-05-09 12:14:55 05b4b1f2a937c06c90db70c09890038f6c98ec40"
SHA1 for sqlite3.c: 85e4e1c08c7df28ef61bb9759a0d466e0eefbaa2