SQLite Release 3.8.1 On 2013-10-17 (3.8.1)

• Added the unlikely() and likelihood() SQL functions to be used as hints to the query planner.
• Enhancements to the query planner:
  • Take into account the fact WHERE clause terms that cannot be used with indices still probably reduce the number of output rows.
  • Estimate the sizes of table and index rows and use the smallest applicable B-Tree for full scans and "count(*)" operations.
• Added the soft_heap_limit pragma.
• Added support for SQLITE_ENABLE_STAT4
• Added support for "sz=NNN" parameters at the end of sqlite_stat1.stat fields used to specify the average length in bytes for table and index rows.
• Avoid running foreign-key constraint checks on an UPDATE if none of the modified columns are associated with foreign keys.
• Added the SQLITE_MINIMUM_FILE_DESCRIPTOR compile-time option
• Added the win32-longpath VFS on windows, permitting filenames up to 32K characters in length.
• The Date And Time Functions are enhanced so that the current time (ex: julianday('now')) is always the same for multiple function invocations within the same sqlite3_step() call.
• Add the "totype.c" extension, implementing the tointeger() and toreal() SQL functions.
• FTS4 queries are better able to make use of docid<$limit constraints to limit the amount of I/O required.
• Added the hidden fts4aux languageid column to the fts4aux virtual table.
• The VACUUM command packs the database about 1% tighter.
• The sqlite3_analyzer utility program is updated to provide better descriptions and to compute a more accurate estimate for "Non-sequential pages"
• Refactor the implementation of PRAGMA statements to improve parsing performance.
• The directory used to hold temporary files on unix can now be set using the SQLITE_TMPDIR environment variable, which takes precedence over the TMPDIR environment variable. The sqlite3_temp_directory global variable still has higher precedence than both environment variables, however.
• Added the PRAGMA stats statement.
• Bug fix: Return the correct answer for "SELECT count(*) FROM table" even if there is a partial index on the table. Ticket a5c8ed66ca.
• SQLITE_SOURCE_ID: "2013-10-17 12:57:35 c78be6d786c19073b3a6730dfe3fb1be54f5657a"
• SHA1 for sqlite3.c: 0a54d76566728c2ba96292a49b138e4f69a7c391

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