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## SQLite Release 3.13.0 On 2016-05-18

1. Postpone I/O associated with TEMP files for as long as possible, with the hope that the I/O can ultimately be avoided completely.
2. Merged the session extension into trunk.
3. Added the ".auth ON|OFF" command to the command-line shell.
4. Added the "--indent" option to the ".schema" and ".fullschema" commands of the command-line shell, to turn on pretty-printing.
5. Added the ".eqp full" option to the command-line shell, that does both EXPLAIN and EXPLAIN QUERY PLAN on each statement that is evaluated.
6. Improved unicode filename handling in the command-line shell on Windows.
7. Improved resistance against goofy query planner decisions caused by incomplete or incorrect modifications to the sqlite_stat1 table by the application.
8. 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.
9. 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:

10. 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
11. 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.
12. 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.
13. 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.

    Hashes:

14. SQLITE_SOURCE_ID: "2016-05-18 10:57:30 fc49f556e48970561d7ab6a2f24fdd7d9eb81ff2"
15. SHA1 for sqlite3.c: 9b9171b1e6ce7a980e6b714e9c0d9112657ad552

    Bug fixes backported into patch release 3.8.6 (2014-08-15):

16. Added support for hexadecimal integer literals in the SQL parser. (Ex: 0x123abc)
17. Enhanced the PRAGMA integrity_check command to detect UNIQUE and NOT NULL constraint violations.
18. Increase the maximum value of SQLITE_MAX_ATTACHED from 62 to 125.
19. Increase the timeout in WAL mode before issuing an SQLITE_PROTOCOL error from 1 second to 10 seconds.
20. Added the likely(X) SQL function.
21. The unicode61 tokenizer is now included in FTS4 by default.
22. Trigger automatic reprepares on all prepared statements when ANALYZE is run.
23. Added a new loadable extension source code file to the source tree: fileio.c
24. Add extension functions readfile(X) and writefile(X,Y) (using code copy/pasted from fileio.c in the previous bullet) to the command-line shell.
25. Added the .fullschema dot-command to the command-line shell.

    Performance Enhancements:

26. Deactivate the DISTINCT keyword on subqueries on the right-hand side of the IN operator.
27. Add the capability of evaluating an IN operator as a sequence of comparisons as an alternative to using a table lookup. Use the sequence of comparisons implementation in circumstances where it is likely to be faster, such as when the right-hand side of the IN operator is small and/or changes frequently.
28. The query planner now uses sqlite_stat4 information (created by ANALYZE) to help determine if the skip-scan optimization is appropriate.
29. Ensure that the query planner never tries to use a self-made transient index in place of a schema-defined index.
30. Other minor tweaks to improve the quality of VDBE code.

    Bug Fixes:

31. Fix a bug in CREATE UNIQUE INDEX, introduced when WITHOUT ROWID support added in version 3.8.2, that allows a non-unique NOT NULL column to be given a UNIQUE index. Ticket 9a6daf340df99ba93c
32. Fix a bug in R-Tree extension, introduced in the previous release, that can cause an incorrect results for queries that use the rowid of the R-Tree on the left-hand side of an IN operator. Ticket d2889096e7bdeac6.
33. Fix the sqlite3_stmt_busy() interface so that it gives the correct answer for ROLLBACK statements that have been stepped but never reset.
34. Fix a bug in that would cause a null pointer to be dereferenced if a column with a DEFAULT that is an aggregate function tried to usee its DEFAULT. Ticket 3a88d85f36704eebe1
35. CSV output from the command-line shell now always uses CRNL for the row separator and avoids inserting CR in front of NLs contained in data.
36. Fix a column affinity problem with the IN operator. Ticket 9a8b09f8e6.
37. Fix the ANALYZE command so that it adds correct samples for WITHOUT ROWID tables in the sqlite_stat4 table. Ticket b2fa5424e6fcb15.

    Bug fixes backported into patch release 3.8.5 (2014-06-04):

38. Added support for partial sorting by index.
39. Enhance the query planner so that it always prefers an index that uses a superset of WHERE clause terms relative to some other index.
40. Improvements to the automerge command of FTS4 to better control the index size for a full-text index that is subject to a large number of updates.
41. Added the sqlite3_rtree_query_callback() interface to R-Tree extension
42. Added new URI query parameters "nolock" and "immutable".
43. Use less memory by not remembering CHECK constraints on read-only database connections.
44. Enable the OR optimization for WITHOUT ROWID tables.
45. Render expressions of the form "x IN (?)" (with a single value in the list on the right-hand side of the IN operator) as if they where "x==?", Similarly optimize "x NOT IN (?)"
46. Add the ".system" and ".once" commands to the command-line shell.
47. Added the SQLITE_IOCAP_IMMUTABLE bit to the set of bits that can be returned by the xDeviceCharacteristics method of a VFS.
48. Added the SQLITE_TESTCTRL_BYTEORDER test control.

    Bug Fixes:

49. OFFSET clause ignored on queries without a FROM clause. Ticket 07d6a0453d
50. Assertion fault on queries involving expressions of the form "x IN (?)". Ticket e39d032577.
51. Incorrect column datatype reported. Ticket a8a0d2996a
52. Duplicate row returned on a query against a table with more than 16 indices, each on a separate column, and all used via OR-connected constraints. Ticket 10fb063b11
53. Partial index causes assertion fault on UPDATE OR REPLACE. Ticket 2ea3e9fe63
54. Crash when calling undocumented SQL function sqlite_rename_parent() with NULL parameters. Ticket 264b970c43
55. ORDER BY ignored if the query has an identical GROUP BY. Ticket b75a9ca6b0
56. The group_concat(x,'') SQL function returns NULL instead of an empty string when all inputs are empty strings. Ticket 55746f9e65
57. Fix a bug in the VDBE code generator that caused crashes when doing an INSERT INTO ... SELECT statement where the number of columns being inserted is larger than the number of columns in the destination table. Ticket e9654505cfd
58. Fix a problem in CSV import in the command-line shell where if the leftmost field of the first row in the CSV file was both zero bytes in size and unquoted no data would be imported.
59. Fix a problem in FTS4 where the left-most column that contained the notindexed column name as a prefix was not indexed rather than the column whose name matched exactly.
60. Fix the sqlite3_db_readonly() interface so that it returns true if the database is read-only due to the file format write version number being too large.

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.