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SQLite Release 3.35.4 On 2021-04-02
Changes in version 3.35.0 (2021-03-12):
- Added built-in SQL math functions(). (Requires the
-DSQLITE_ENABLE_MATH_FUNCTIONS compile-time option.)
- Added support for ALTER TABLE DROP COLUMN.
- Generalize UPSERT:
- Allow multiple ON CONFLICT clauses that are evaluated in order,
- The final ON CONFLICT clause may omit the conflict target and
yet still use DO UPDATE.
- Add support for the RETURNING clause on DELETE, INSERT, and
- Use less memory when running VACUUM on databases containing very large
TEXT or BLOB values. It is no longer necessary to hold the entire TEXT
or BLOB in memory all at once.
- Add support for the MATERIALIZED and NOT MATERIALIZED hints when
specifying common table expressions. The default behavior was
formerly NOT MATERIALIZED, but is now changed to MATERIALIZED for
CTEs that are used more than once.
- The SQLITE_DBCONFIG_ENABLE_TRIGGER and SQLITE_DBCONFIG_ENABLE_VIEW
settings are modified so that they only control triggers and views
in the main database schema or in attached database schemas and not in
the TEMP schema. TEMP triggers and views are always allowed.
- Query planner/optimizer improvements:
- Enhancements to the min/max optimization so that it works better
with the IN operator and the OP_SeekScan optimization of the
- Attempt to process EXISTS operators in the WHERE clause as if
they were IN operators, in cases where this is a valid transformation
and seems likely to improve performance.
- Allow UNION ALL sub-queries to be flattened even if the parent query is a join.
- Use an index, if appropriate, on IS NOT NULL expressions in the WHERE clause,
even if STAT4 is disabled.
- Expressions of the form "x IS NULL" or "x IS NOT NULL" might be converted to simply
FALSE or TRUE, if "x" is a column that has a "NOT NULL" constraint and is not
involved in an outer join.
- Avoid checking foreign key constraints on an UPDATE statement if the UPDATE does
not modify any columns associated with the foreign key.
- Allow WHERE terms to be pushed down into sub-queries
that contain window functions,
as long as the WHERE term is made up of entirely of constants and copies of expressions
found in the PARTITION BY clauses of all window functions in the sub-query.
- CLI enhancements:
- Enhance the ".stats" command to accept new arguments "stmt" and
"vmstep", causing prepare statement statistics and only the
virtual-machine step count to be shown, respectively.
- Add the ".filectrl data_version" command.
- Enhance the ".once" and ".output" commands so that if the destination argument
begins with "|" (indicating that output is redirected into a pipe) then the
argument does not need to be quoted.
- Bug fixes:
- Fix a potential NULL pointer dereference when processing a
syntactically incorrect SELECT statement with a correlated WHERE
clause and a "HAVING 0" clause. (Also fixed in the 3.34.1 patch release.)
- Fix a bug in the IN-operator optimization
of version 3.33.0 that can cause an incorrect answer.
- Fix incorrect answers from the LIKE operator if the pattern ends with "%" and there
is an "ESCAPE '_'" clause.
Additional changes in version 3.35.1 (2021-03-15):
- Fix a bug in the new DROP COLUMN
feature when used on columns that are indexed and that are quoted in the index
- Improve the built-in documentation for the .dump command in the CLI.
Additional changes in version 3.35.2 (2021-03-17):
- Fix a problem in the
extension that was introduced into version 3.35.0.
- Ensure that date/time functions with no arguments (which generate
responses that depend on the current time) are treated as
non-deterministic functions. Ticket
- Fix a problem in the sqldiff utility program having to do with
unusual whitespace characters in a virtual table definition.
- Limit the new UNION ALL optimization described by item 8c in the
3.35.0 release so that it does not try to make too many new subqueries.
See forum thread 140a67d3d2
Additional changes in version 3.35.3 (2021-03-26):
- Enhance the OP_OpenDup opcode of the bytecode engine so that it works even if the
cursor being duplicated itself came from OP_OpenDup. Fix for
This problem only came to light due to the recent MATERIALIZED hint enhancement.
- When materializing correlated common table expressions, do so separately for each
use case, as that is required for correctness. This fixes a problem that was
introduced by the MATERIALIZED hint enhancement.
- Fix a problem in the filename normalizer of the unix VFS.
- Fix the "box" output mode in the CLI so that it works with statements that
returns one or more rows of zero columns (such as PRAGMA incremental_vacuum).
Forum post afbbcb5b72.
- Improvements to error messages generated by faulty common table expressions.
Forum post aa5a0431c99e.
- Fix some incorrect assert() statements.
- Fix to the SELECT statement syntax diagram so that the FROM clause
syntax is shown correctly.
Forum post 9ed02582fe.
- Fix the EBCDIC character classifier so that it understands newlines as whitespace.
Forum post 58540ce22dcd.
- Improvements the xBestIndex method in the implementation of the
(unsupported) wholenumber virtual table
extension so that it does a better job of convincing the query planner to
avoid trying to materialize a table with an infinite number of rows.
Forum post b52a020ce4.
Additional changes in version 3.35.4 (2021-04-02):
- Fix a defect in the query planner optimization identified by
item 8b above. Ticket
- Fix a defect in the new RETURNING syntax. Ticket
- Fix the new RETURNING feature so that it raises an error if one of
the terms in the RETURNING clause references a unknown table, instead
of silently ignoring that error.
- Fix an assertion associated with aggregate function processing that
was incorrectly triggered by the push-down optimization.
- SQLITE_SOURCE_ID: 2021-04-02 15:20:15 5d4c65779dab868b285519b19e4cf9d451d50c6048f06f653aa701ec212df45e
- SHA3-256 for sqlite3.c: 528b8a26bf5ffd4c7b4647b5b799f86e8fb1a075f715b87a414e94fba3d09dbe
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.
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