- SQLite 3.26.0:
* Optimization: When doing an UPDATE on a table with indexes on
expressions, do not update the expression indexes if they do
not refer to any of the columns of the table being updated.
* Allow the xBestIndex() method of virtual table implementations
to return SQLITE_CONSTRAINT to indicate that the proposed query
plan is unusable and should not be given further consideration.
* Added the SQLITE_DBCONFIG_DEFENSIVE option which disables the
ability to create corrupt database files using ordinary SQL.
* Added support for read-only shadow tables when the
SQLITE_DBCONFIG_DEFENSIVE option is enabled.
* Added the PRAGMA legacy_alter_table command, which if enabled
causes the ALTER TABLE command to behave like older version of
SQLite (prior to version 3.25.0) for compatibility.
* Added PRAGMA table_xinfo that works just like PRAGMA table_info
except that it also shows hidden columns in virtual tables.
* Added the explain virtual table as a run-time loadable
extension.
* Add a limit counter to the query planner to prevent excessive
sqlite3_prepare() times for certain pathological SQL inputs.
* Added support for the sqlite3_normalized_sql() interface, when
compiling with SQLITE_ENABLE_NORMALIZE.
* Enhanced triggers so that they can use table-valued functions
that exist in schemas other than the schema where the trigger
is defined.
* Improvements to the ".help" command in the CLI.
* The SQLITE_HISTORY environment variable, if it exists,
specifies the name of the command-line editing history file.
* The --deserialize option associated with opening a new database
in the CLI cause the database file to be read into memory and
accessed using the sqlite3_deserialize() API. This simplifies
running tests on a database without modifying the file on disk.