Changes 3.7.12:
* Add the SQLITE_DBSTATUS_CACHE_WRITE option for sqlite3_db_status().
* Optimize the typeof() and length() SQL functions so that they avoid unnecessary reading of database content from disk.
* Add the FTS4 "merge" command, the FTS4 "automerge" command, and the FTS4 "integrity-check" command.
* Report the name of specific CHECK constraints that fail.
* In the command-line shell, use popen() instead of fopen() if the first character of the argument to the ".output" command is "|".
* Make use of OVERLAPPED in the windows VFS to avoid some system calls and thereby obtain a performance improvement.
* More aggressive optimization of the AND operator when one side or the other is always false.
* Improved performance of queries with many OR-connected terms in the WHERE clause that can all be indexed.
* Add the SQLITE_RTREE_INT_ONLY compile-time option to force the R*Tree Extension Module to use integer instead of floating point values for both storage and computation.
* Enhance the PRAGMA integrity_check command to use much less memory when processing multi-gigabyte databases.
* New interfaces added to the test_quota.c add-on module.
* Added the ".trace" dot-command to the command-line shell.
* Allow virtual table constructors to be invoked recursively.
* Improved optimization of ORDER BY clauses on compound queries.
* Improved optimization of aggregate subqueries contained within an aggregate query.
* Bug fix: Fix the RELEASE command so that it does not cancel pending queries. This repairs a problem introduced in 3.7.11.
* Bug fix: Do not discard the DISTINCT as superfluous unless a subset of the result set is subject to a UNIQUE constraint and it none of the columns in that subset can be NULL.
* Bug fix: Do not optimize away an ORDER BY clause that has the same terms as a UNIQUE index unless those terms are also NOT NULL.


(adam)