docs: add about BaseConnection::transException()

Author: kenjis

user_guide_src/source/changelogs/v4.3.0.rst

@@ -235,6 +235,8 @@ Others
 - Improved data returned by :ref:`BaseConnection::getForeignKeyData() <metadata-getforeignkeydata>`. All DBMS returns the same structure.
 - SQLite :ref:`BaseConnection::getIndexData() <db-metadata-getindexdata>` now can return pseudo index named ``PRIMARY`` for `AUTOINCREMENT` column, and each returned index data has ``type`` property.
 - ``BasePreparedQuery::close()`` now deallocates the prepared statement in all DBMS. Previously, they were not deallocated in Postgre, SQLSRV and OCI8. See :ref:`database-queries-stmt-close`.
+- Added ``BaseConnection::transException()`` to throw exceptinons during transactions.
+  See :ref:`transactions-throwing-exceptions`
 
 Model
 =====

user_guide_src/source/database/transactions.rst

@@ -75,6 +75,25 @@ If the ``DBDebug`` is false, you can manage your own errors like this:
 
 .. literalinclude:: transactions/003.php
 
+.. _transactions-throwing-exceptions:
+
+Throwing Exceptions
+===================
+
+.. versionadded:: 4.3.0
+
+.. note::
+    Since v4.3.0, during transactions, exceptions are not thrown by default
+    even if ``DBDebug`` is true.
+
+If you want an exception to be thrown when a query error occurs, you can use
+``$this->db->transException(true)``:
+
+.. literalinclude:: transactions/008.php
+
+If a query error occurs, all the queries will be rolled backed, and a
+``DatabaseException`` will be thrown.
+
 Disabling Transactions
 ======================
 

user_guide_src/source/installation/upgrade_430.rst

@@ -51,6 +51,9 @@ Database Exception Changes
 - The exception classes may be changed when database errors occur. If you catch the exceptions,
   you must confirm that your code can catch the exceptions.
 - Now a few exceptions will be thrown even if ``CI_DEBUG`` is false.
+- During transactions, exceptions are not thrown by default even if ``DBDebug`` is true. If you want
+  exceptions to be thrown, you need to call ``transException(true)``.
+  See :ref:`transactions-throwing-exceptions`.
 - See :ref:`exceptions-when-database-errors-occur` for details.
 
 HTTP Status Code and Exit Code of Uncaught Exceptions