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+# dialects/oracle/cx_oracle.py
+# Copyright (C) 2005-2025 the SQLAlchemy authors and contributors
+# <see AUTHORS file>
+#
+# This module is part of SQLAlchemy and is released under
+# the MIT License: https://www.opensource.org/licenses/mit-license.php
+# mypy: ignore-errors
+
+
+r""".. dialect:: oracle+cx_oracle
+    :name: cx-Oracle
+    :dbapi: cx_oracle
+    :connectstring: oracle+cx_oracle://user:pass@hostname:port[/dbname][?service_name=<service>[&key=value&key=value...]]
+    :url: https://oracle.github.io/python-cx_Oracle/
+
+Description
+-----------
+
+cx_Oracle was the original driver for Oracle Database. It was superseded by
+python-oracledb which should be used instead.
+
+DSN vs. Hostname connections
+-----------------------------
+
+cx_Oracle provides several methods of indicating the target database.  The
+dialect translates from a series of different URL forms.
+
+Hostname Connections with Easy Connect Syntax
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Given a hostname, port and service name of the target database, for example
+from Oracle Database's Easy Connect syntax then connect in SQLAlchemy using the
+``service_name`` query string parameter::
+
+    engine = create_engine(
+        "oracle+cx_oracle://scott:tiger@hostname:port?service_name=myservice&encoding=UTF-8&nencoding=UTF-8"
+    )
+
+Note that the default driver value for encoding and nencoding was changed to
+“UTF-8” in cx_Oracle 8.0 so these parameters can be omitted when using that
+version, or later.
+
+To use a full Easy Connect string, pass it as the ``dsn`` key value in a
+:paramref:`_sa.create_engine.connect_args` dictionary::
+
+    import cx_Oracle
+
+    e = create_engine(
+        "oracle+cx_oracle://@",
+        connect_args={
+            "user": "scott",
+            "password": "tiger",
+            "dsn": "hostname:port/myservice?transport_connect_timeout=30&expire_time=60",
+        },
+    )
+
+Connections with tnsnames.ora or to Oracle Autonomous Database
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Alternatively, if no port, database name, or service name is provided, the
+dialect will use an Oracle Database DSN "connection string".  This takes the
+"hostname" portion of the URL as the data source name.  For example, if the
+``tnsnames.ora`` file contains a TNS Alias of ``myalias`` as below:
+
+.. sourcecode:: text
+
+    myalias =
+      (DESCRIPTION =
+        (ADDRESS = (PROTOCOL = TCP)(HOST = mymachine.example.com)(PORT = 1521))
+        (CONNECT_DATA =
+          (SERVER = DEDICATED)
+          (SERVICE_NAME = orclpdb1)
+        )
+      )
+
+The cx_Oracle dialect connects to this database service when ``myalias`` is the
+hostname portion of the URL, without specifying a port, database name or
+``service_name``::
+
+    engine = create_engine("oracle+cx_oracle://scott:tiger@myalias")
+
+Users of Oracle Autonomous Database should use this syntax. If the database is
+configured for mutural TLS ("mTLS"), then you must also configure the cloud
+wallet as shown in cx_Oracle documentation `Connecting to Autononmous Databases
+<https://cx-oracle.readthedocs.io/en/latest/user_guide/connection_handling.html#autonomousdb>`_.
+
+SID Connections
+^^^^^^^^^^^^^^^
+
+To use Oracle Database's obsolete System Identifier connection syntax, the SID
+can be passed in a "database name" portion of the URL::
+
+    engine = create_engine(
+        "oracle+cx_oracle://scott:tiger@hostname:port/dbname"
+    )
+
+Above, the DSN passed to cx_Oracle is created by ``cx_Oracle.makedsn()`` as
+follows::
+
+    >>> import cx_Oracle
+    >>> cx_Oracle.makedsn("hostname", 1521, sid="dbname")
+    '(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=hostname)(PORT=1521))(CONNECT_DATA=(SID=dbname)))'
+
+Note that although the SQLAlchemy syntax ``hostname:port/dbname`` looks like
+Oracle's Easy Connect syntax it is different. It uses a SID in place of the
+service name required by Easy Connect.  The Easy Connect syntax does not
+support SIDs.
+
+Passing cx_Oracle connect arguments
+-----------------------------------
+
+Additional connection arguments can usually be passed via the URL query string;
+particular symbols like ``SYSDBA`` are intercepted and converted to the correct
+symbol::
+
+    e = create_engine(
+        "oracle+cx_oracle://user:pass@dsn?encoding=UTF-8&nencoding=UTF-8&mode=SYSDBA&events=true"
+    )
+
+.. versionchanged:: 1.3 the cx_Oracle dialect now accepts all argument names
+   within the URL string itself, to be passed to the cx_Oracle DBAPI.   As
+   was the case earlier but not correctly documented, the
+   :paramref:`_sa.create_engine.connect_args` parameter also accepts all
+   cx_Oracle DBAPI connect arguments.
+
+To pass arguments directly to ``.connect()`` without using the query
+string, use the :paramref:`_sa.create_engine.connect_args` dictionary.
+Any cx_Oracle parameter value and/or constant may be passed, such as::
+
+    import cx_Oracle
+
+    e = create_engine(
+        "oracle+cx_oracle://user:pass@dsn",
+        connect_args={
+            "encoding": "UTF-8",
+            "nencoding": "UTF-8",
+            "mode": cx_Oracle.SYSDBA,
+            "events": True,
+        },
+    )
+
+Note that the default driver value for ``encoding`` and ``nencoding`` was
+changed to "UTF-8" in cx_Oracle 8.0 so these parameters can be omitted when
+using that version, or later.
+
+Options consumed by the SQLAlchemy cx_Oracle dialect outside of the driver
+--------------------------------------------------------------------------
+
+There are also options that are consumed by the SQLAlchemy cx_oracle dialect
+itself.  These options are always passed directly to :func:`_sa.create_engine`
+, such as::
+
+    e = create_engine(
+        "oracle+cx_oracle://user:pass@dsn", coerce_to_decimal=False
+    )
+
+The parameters accepted by the cx_oracle dialect are as follows:
+
+* ``arraysize`` - set the cx_oracle.arraysize value on cursors; defaults
+  to ``None``, indicating that the driver default should be used (typically
+  the value is 100).  This setting controls how many rows are buffered when
+  fetching rows, and can have a significant effect on performance when
+  modified.
+
+  .. versionchanged:: 2.0.26 - changed the default value from 50 to None,
+    to use the default value of the driver itself.
+
+* ``auto_convert_lobs`` - defaults to True; See :ref:`cx_oracle_lob`.
+
+* ``coerce_to_decimal`` - see :ref:`cx_oracle_numeric` for detail.
+
+* ``encoding_errors`` - see :ref:`cx_oracle_unicode_encoding_errors` for detail.
+
+.. _cx_oracle_sessionpool:
+
+Using cx_Oracle SessionPool
+---------------------------
+
+The cx_Oracle driver provides its own connection pool implementation that may
+be used in place of SQLAlchemy's pooling functionality. The driver pool
+supports Oracle Database features such dead connection detection, connection
+draining for planned database downtime, support for Oracle Application
+Continuity and Transparent Application Continuity, and gives support for
+Database Resident Connection Pooling (DRCP).
+
+Using the driver pool can be achieved by using the
+:paramref:`_sa.create_engine.creator` parameter to provide a function that
+returns a new connection, along with setting
+:paramref:`_sa.create_engine.pool_class` to ``NullPool`` to disable
+SQLAlchemy's pooling::
+
+    import cx_Oracle
+    from sqlalchemy import create_engine
+    from sqlalchemy.pool import NullPool
+
+    pool = cx_Oracle.SessionPool(
+        user="scott",
+        password="tiger",
+        dsn="orclpdb",
+        min=1,
+        max=4,
+        increment=1,
+        threaded=True,
+        encoding="UTF-8",
+        nencoding="UTF-8",
+    )
+
+    engine = create_engine(
+        "oracle+cx_oracle://", creator=pool.acquire, poolclass=NullPool
+    )
+
+The above engine may then be used normally where cx_Oracle's pool handles
+connection pooling::
+
+    with engine.connect() as conn:
+        print(conn.scalar("select 1 from dual"))
+
+As well as providing a scalable solution for multi-user applications, the
+cx_Oracle session pool supports some Oracle features such as DRCP and
+`Application Continuity
+<https://cx-oracle.readthedocs.io/en/latest/user_guide/ha.html#application-continuity-ac>`_.
+
+Note that the pool creation parameters ``threaded``, ``encoding`` and
+``nencoding`` were deprecated in later cx_Oracle releases.
+
+Using Oracle Database Resident Connection Pooling (DRCP)
+--------------------------------------------------------
+
+When using Oracle Database's DRCP, the best practice is to pass a connection
+class and "purity" when acquiring a connection from the SessionPool.  Refer to
+the `cx_Oracle DRCP documentation
+<https://cx-oracle.readthedocs.io/en/latest/user_guide/connection_handling.html#database-resident-connection-pooling-drcp>`_.
+
+This can be achieved by wrapping ``pool.acquire()``::
+
+    import cx_Oracle
+    from sqlalchemy import create_engine
+    from sqlalchemy.pool import NullPool
+
+    pool = cx_Oracle.SessionPool(
+        user="scott",
+        password="tiger",
+        dsn="orclpdb",
+        min=2,
+        max=5,
+        increment=1,
+        threaded=True,
+        encoding="UTF-8",
+        nencoding="UTF-8",
+    )
+
+
+    def creator():
+        return pool.acquire(
+            cclass="MYCLASS", purity=cx_Oracle.ATTR_PURITY_SELF
+        )
+
+
+    engine = create_engine(
+        "oracle+cx_oracle://", creator=creator, poolclass=NullPool
+    )
+
+The above engine may then be used normally where cx_Oracle handles session
+pooling and Oracle Database additionally uses DRCP::
+
+    with engine.connect() as conn:
+        print(conn.scalar("select 1 from dual"))
+
+.. _cx_oracle_unicode:
+
+Unicode
+-------
+
+As is the case for all DBAPIs under Python 3, all strings are inherently
+Unicode strings. In all cases however, the driver requires an explicit
+encoding configuration.
+
+Ensuring the Correct Client Encoding
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The long accepted standard for establishing client encoding for nearly all
+Oracle Database related software is via the `NLS_LANG
+<https://www.oracle.com/database/technologies/faq-nls-lang.html>`_ environment
+variable.  Older versions of cx_Oracle use this environment variable as the
+source of its encoding configuration.  The format of this variable is
+Territory_Country.CharacterSet; a typical value would be
+``AMERICAN_AMERICA.AL32UTF8``.  cx_Oracle version 8 and later use the character
+set "UTF-8" by default, and ignore the character set component of NLS_LANG.
+
+The cx_Oracle driver also supported a programmatic alternative which is to pass
+the ``encoding`` and ``nencoding`` parameters directly to its ``.connect()``
+function.  These can be present in the URL as follows::
+
+    engine = create_engine(
+        "oracle+cx_oracle://scott:tiger@tnsalias?encoding=UTF-8&nencoding=UTF-8"
+    )
+
+For the meaning of the ``encoding`` and ``nencoding`` parameters, please
+consult
+`Characters Sets and National Language Support (NLS) <https://cx-oracle.readthedocs.io/en/latest/user_guide/globalization.html#globalization>`_.
+
+.. seealso::
+
+    `Characters Sets and National Language Support (NLS) <https://cx-oracle.readthedocs.io/en/latest/user_guide/globalization.html#globalization>`_
+    - in the cx_Oracle documentation.
+
+
+Unicode-specific Column datatypes
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The Core expression language handles unicode data by use of the
+:class:`.Unicode` and :class:`.UnicodeText` datatypes.  These types correspond
+to the VARCHAR2 and CLOB Oracle Database datatypes by default.  When using
+these datatypes with Unicode data, it is expected that the database is
+configured with a Unicode-aware character set, as well as that the ``NLS_LANG``
+environment variable is set appropriately (this applies to older versions of
+cx_Oracle), so that the VARCHAR2 and CLOB datatypes can accommodate the data.
+
+In the case that Oracle Database is not configured with a Unicode character
+set, the two options are to use the :class:`_types.NCHAR` and
+:class:`_oracle.NCLOB` datatypes explicitly, or to pass the flag
+``use_nchar_for_unicode=True`` to :func:`_sa.create_engine`, which will cause
+the SQLAlchemy dialect to use NCHAR/NCLOB for the :class:`.Unicode` /
+:class:`.UnicodeText` datatypes instead of VARCHAR/CLOB.
+
+.. versionchanged:: 1.3 The :class:`.Unicode` and :class:`.UnicodeText`
+   datatypes now correspond to the ``VARCHAR2`` and ``CLOB`` Oracle Database
+   datatypes unless the ``use_nchar_for_unicode=True`` is passed to the dialect
+   when :func:`_sa.create_engine` is called.
+
+
+.. _cx_oracle_unicode_encoding_errors:
+
+Encoding Errors
+^^^^^^^^^^^^^^^
+
+For the unusual case that data in Oracle Database is present with a broken
+encoding, the dialect accepts a parameter ``encoding_errors`` which will be
+passed to Unicode decoding functions in order to affect how decoding errors are
+handled.  The value is ultimately consumed by the Python `decode
+<https://docs.python.org/3/library/stdtypes.html#bytes.decode>`_ function, and
+is passed both via cx_Oracle's ``encodingErrors`` parameter consumed by
+``Cursor.var()``, as well as SQLAlchemy's own decoding function, as the
+cx_Oracle dialect makes use of both under different circumstances.
+
+.. versionadded:: 1.3.11
+
+
+.. _cx_oracle_setinputsizes:
+
+Fine grained control over cx_Oracle data binding performance with setinputsizes
+-------------------------------------------------------------------------------
+
+The cx_Oracle DBAPI has a deep and fundamental reliance upon the usage of the
+DBAPI ``setinputsizes()`` call.  The purpose of this call is to establish the
+datatypes that are bound to a SQL statement for Python values being passed as
+parameters.  While virtually no other DBAPI assigns any use to the
+``setinputsizes()`` call, the cx_Oracle DBAPI relies upon it heavily in its
+interactions with the Oracle Database client interface, and in some scenarios
+it is not possible for SQLAlchemy to know exactly how data should be bound, as
+some settings can cause profoundly different performance characteristics, while
+altering the type coercion behavior at the same time.
+
+Users of the cx_Oracle dialect are **strongly encouraged** to read through
+cx_Oracle's list of built-in datatype symbols at
+https://cx-oracle.readthedocs.io/en/latest/api_manual/module.html#database-types.
+Note that in some cases, significant performance degradation can occur when
+using these types vs. not, in particular when specifying ``cx_Oracle.CLOB``.
+
+On the SQLAlchemy side, the :meth:`.DialectEvents.do_setinputsizes` event can
+be used both for runtime visibility (e.g. logging) of the setinputsizes step as
+well as to fully control how ``setinputsizes()`` is used on a per-statement
+basis.
+
+.. versionadded:: 1.2.9 Added :meth:`.DialectEvents.setinputsizes`
+
+
+Example 1 - logging all setinputsizes calls
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The following example illustrates how to log the intermediary values from a
+SQLAlchemy perspective before they are converted to the raw ``setinputsizes()``
+parameter dictionary.  The keys of the dictionary are :class:`.BindParameter`
+objects which have a ``.key`` and a ``.type`` attribute::
+
+    from sqlalchemy import create_engine, event
+
+    engine = create_engine("oracle+cx_oracle://scott:tiger@host/xe")
+
+
+    @event.listens_for(engine, "do_setinputsizes")
+    def _log_setinputsizes(inputsizes, cursor, statement, parameters, context):
+        for bindparam, dbapitype in inputsizes.items():
+            log.info(
+                "Bound parameter name: %s  SQLAlchemy type: %r DBAPI object: %s",
+                bindparam.key,
+                bindparam.type,
+                dbapitype,
+            )
+
+Example 2 - remove all bindings to CLOB
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The ``CLOB`` datatype in cx_Oracle incurs a significant performance overhead,
+however is set by default for the ``Text`` type within the SQLAlchemy 1.2
+series.   This setting can be modified as follows::
+
+    from sqlalchemy import create_engine, event
+    from cx_Oracle import CLOB
+
+    engine = create_engine("oracle+cx_oracle://scott:tiger@host/xe")
+
+
+    @event.listens_for(engine, "do_setinputsizes")
+    def _remove_clob(inputsizes, cursor, statement, parameters, context):
+        for bindparam, dbapitype in list(inputsizes.items()):
+            if dbapitype is CLOB:
+                del inputsizes[bindparam]
+
+.. _cx_oracle_lob:
+
+LOB Datatypes
+--------------
+
+LOB datatypes refer to the "large object" datatypes such as CLOB, NCLOB and
+BLOB. Modern versions of cx_Oracle is optimized for these datatypes to be
+delivered as a single buffer. As such, SQLAlchemy makes use of these newer type
+handlers by default.
+
+To disable the use of newer type handlers and deliver LOB objects as classic
+buffered objects with a ``read()`` method, the parameter
+``auto_convert_lobs=False`` may be passed to :func:`_sa.create_engine`,
+which takes place only engine-wide.
+
+.. _cx_oracle_returning:
+
+RETURNING Support
+-----------------
+
+The cx_Oracle dialect implements RETURNING using OUT parameters.
+The dialect supports RETURNING fully.
+
+Two Phase Transactions Not Supported
+------------------------------------
+
+Two phase transactions are **not supported** under cx_Oracle due to poor driver
+support. The newer :ref:`oracledb` dialect however **does** support two phase
+transactions.
+
+.. _cx_oracle_numeric:
+
+Precision Numerics
+------------------
+
+SQLAlchemy's numeric types can handle receiving and returning values as Python
+``Decimal`` objects or float objects.  When a :class:`.Numeric` object, or a
+subclass such as :class:`.Float`, :class:`_oracle.DOUBLE_PRECISION` etc. is in
+use, the :paramref:`.Numeric.asdecimal` flag determines if values should be
+coerced to ``Decimal`` upon return, or returned as float objects.  To make
+matters more complicated under Oracle Database, the ``NUMBER`` type can also
+represent integer values if the "scale" is zero, so the Oracle
+Database-specific :class:`_oracle.NUMBER` type takes this into account as well.
+
+The cx_Oracle dialect makes extensive use of connection- and cursor-level
+"outputtypehandler" callables in order to coerce numeric values as requested.
+These callables are specific to the specific flavor of :class:`.Numeric` in
+use, as well as if no SQLAlchemy typing objects are present.  There are
+observed scenarios where Oracle Database may send incomplete or ambiguous
+information about the numeric types being returned, such as a query where the
+numeric types are buried under multiple levels of subquery.  The type handlers
+do their best to make the right decision in all cases, deferring to the
+underlying cx_Oracle DBAPI for all those cases where the driver can make the
+best decision.
+
+When no typing objects are present, as when executing plain SQL strings, a
+default "outputtypehandler" is present which will generally return numeric
+values which specify precision and scale as Python ``Decimal`` objects.  To
+disable this coercion to decimal for performance reasons, pass the flag
+``coerce_to_decimal=False`` to :func:`_sa.create_engine`::
+
+    engine = create_engine("oracle+cx_oracle://dsn", coerce_to_decimal=False)
+
+The ``coerce_to_decimal`` flag only impacts the results of plain string
+SQL statements that are not otherwise associated with a :class:`.Numeric`
+SQLAlchemy type (or a subclass of such).
+
+.. versionchanged:: 1.2  The numeric handling system for cx_Oracle has been
+   reworked to take advantage of newer cx_Oracle features as well
+   as better integration of outputtypehandlers.
+
+"""  # noqa
+from __future__ import annotations
+
+import decimal
+import random
+import re
+
+from . import base as oracle
+from .base import OracleCompiler
+from .base import OracleDialect
+from .base import OracleExecutionContext
+from .types import _OracleDateLiteralRender
+from ... import exc
+from ... import util
+from ...engine import cursor as _cursor
+from ...engine import interfaces
+from ...engine import processors
+from ...sql import sqltypes
+from ...sql._typing import is_sql_compiler
+
+# source:
+# https://github.com/oracle/python-cx_Oracle/issues/596#issuecomment-999243649
+_CX_ORACLE_MAGIC_LOB_SIZE = 131072
+
+
+class _OracleInteger(sqltypes.Integer):
+    def get_dbapi_type(self, dbapi):
+        # see https://github.com/oracle/python-cx_Oracle/issues/
+        # 208#issuecomment-409715955
+        return int
+
+    def _cx_oracle_var(self, dialect, cursor, arraysize=None):
+        cx_Oracle = dialect.dbapi
+        return cursor.var(
+            cx_Oracle.STRING,
+            255,
+            arraysize=arraysize if arraysize is not None else cursor.arraysize,
+            outconverter=int,
+        )
+
+    def _cx_oracle_outputtypehandler(self, dialect):
+        def handler(cursor, name, default_type, size, precision, scale):
+            return self._cx_oracle_var(dialect, cursor)
+
+        return handler
+
+
+class _OracleNumeric(sqltypes.Numeric):
+    is_number = False
+
+    def bind_processor(self, dialect):
+        if self.scale == 0:
+            return None
+        elif self.asdecimal:
+            processor = processors.to_decimal_processor_factory(
+                decimal.Decimal, self._effective_decimal_return_scale
+            )
+
+            def process(value):
+                if isinstance(value, (int, float)):
+                    return processor(value)
+                elif value is not None and value.is_infinite():
+                    return float(value)
+                else:
+                    return value
+
+            return process
+        else:
+            return processors.to_float
+
+    def result_processor(self, dialect, coltype):
+        return None
+
+    def _cx_oracle_outputtypehandler(self, dialect):
+        cx_Oracle = dialect.dbapi
+
+        def handler(cursor, name, default_type, size, precision, scale):
+            outconverter = None
+
+            if precision:
+                if self.asdecimal:
+                    if default_type == cx_Oracle.NATIVE_FLOAT:
+                        # receiving float and doing Decimal after the fact
+                        # allows for float("inf") to be handled
+                        type_ = default_type
+                        outconverter = decimal.Decimal
+                    else:
+                        type_ = decimal.Decimal
+                else:
+                    if self.is_number and scale == 0:
+                        # integer. cx_Oracle is observed to handle the widest
+                        # variety of ints when no directives are passed,
+                        # from 5.2 to 7.0.  See [ticket:4457]
+                        return None
+                    else:
+                        type_ = cx_Oracle.NATIVE_FLOAT
+
+            else:
+                if self.asdecimal:
+                    if default_type == cx_Oracle.NATIVE_FLOAT:
+                        type_ = default_type
+                        outconverter = decimal.Decimal
+                    else:
+                        type_ = decimal.Decimal
+                else:
+                    if self.is_number and scale == 0:
+                        # integer. cx_Oracle is observed to handle the widest
+                        # variety of ints when no directives are passed,
+                        # from 5.2 to 7.0.  See [ticket:4457]
+                        return None
+                    else:
+                        type_ = cx_Oracle.NATIVE_FLOAT
+
+            return cursor.var(
+                type_,
+                255,
+                arraysize=cursor.arraysize,
+                outconverter=outconverter,
+            )
+
+        return handler
+
+
+class _OracleUUID(sqltypes.Uuid):
+    def get_dbapi_type(self, dbapi):
+        return dbapi.STRING
+
+
+class _OracleBinaryFloat(_OracleNumeric):
+    def get_dbapi_type(self, dbapi):
+        return dbapi.NATIVE_FLOAT
+
+
+class _OracleBINARY_FLOAT(_OracleBinaryFloat, oracle.BINARY_FLOAT):
+    pass
+
+
+class _OracleBINARY_DOUBLE(_OracleBinaryFloat, oracle.BINARY_DOUBLE):
+    pass
+
+
+class _OracleNUMBER(_OracleNumeric):
+    is_number = True
+
+
+class _CXOracleDate(oracle._OracleDate):
+    def bind_processor(self, dialect):
+        return None
+
+    def result_processor(self, dialect, coltype):
+        def process(value):
+            if value is not None:
+                return value.date()
+            else:
+                return value
+
+        return process
+
+
+class _CXOracleTIMESTAMP(_OracleDateLiteralRender, sqltypes.TIMESTAMP):
+    def literal_processor(self, dialect):
+        return self._literal_processor_datetime(dialect)
+
+
+class _LOBDataType:
+    pass
+
+
+# TODO: the names used across CHAR / VARCHAR / NCHAR / NVARCHAR
+# here are inconsistent and not very good
+class _OracleChar(sqltypes.CHAR):
+    def get_dbapi_type(self, dbapi):
+        return dbapi.FIXED_CHAR
+
+
+class _OracleNChar(sqltypes.NCHAR):
+    def get_dbapi_type(self, dbapi):
+        return dbapi.FIXED_NCHAR
+
+
+class _OracleUnicodeStringNCHAR(oracle.NVARCHAR2):
+    def get_dbapi_type(self, dbapi):
+        return dbapi.NCHAR
+
+
+class _OracleUnicodeStringCHAR(sqltypes.Unicode):
+    def get_dbapi_type(self, dbapi):
+        return dbapi.LONG_STRING
+
+
+class _OracleUnicodeTextNCLOB(_LOBDataType, oracle.NCLOB):
+    def get_dbapi_type(self, dbapi):
+        # previously, this was dbapi.NCLOB.
+        # DB_TYPE_NVARCHAR will instead be passed to setinputsizes()
+        # when this datatype is used.
+        return dbapi.DB_TYPE_NVARCHAR
+
+
+class _OracleUnicodeTextCLOB(_LOBDataType, sqltypes.UnicodeText):
+    def get_dbapi_type(self, dbapi):
+        # previously, this was dbapi.CLOB.
+        # DB_TYPE_NVARCHAR will instead be passed to setinputsizes()
+        # when this datatype is used.
+        return dbapi.DB_TYPE_NVARCHAR
+
+
+class _OracleText(_LOBDataType, sqltypes.Text):
+    def get_dbapi_type(self, dbapi):
+        # previously, this was dbapi.CLOB.
+        # DB_TYPE_NVARCHAR will instead be passed to setinputsizes()
+        # when this datatype is used.
+        return dbapi.DB_TYPE_NVARCHAR
+
+
+class _OracleLong(_LOBDataType, oracle.LONG):
+    def get_dbapi_type(self, dbapi):
+        return dbapi.LONG_STRING
+
+
+class _OracleString(sqltypes.String):
+    pass
+
+
+class _OracleEnum(sqltypes.Enum):
+    def bind_processor(self, dialect):
+        enum_proc = sqltypes.Enum.bind_processor(self, dialect)
+
+        def process(value):
+            raw_str = enum_proc(value)
+            return raw_str
+
+        return process
+
+
+class _OracleBinary(_LOBDataType, sqltypes.LargeBinary):
+    def get_dbapi_type(self, dbapi):
+        # previously, this was dbapi.BLOB.
+        # DB_TYPE_RAW will instead be passed to setinputsizes()
+        # when this datatype is used.
+        return dbapi.DB_TYPE_RAW
+
+    def bind_processor(self, dialect):
+        return None
+
+    def result_processor(self, dialect, coltype):
+        if not dialect.auto_convert_lobs:
+            return None
+        else:
+            return super().result_processor(dialect, coltype)
+
+
+class _OracleInterval(oracle.INTERVAL):
+    def get_dbapi_type(self, dbapi):
+        return dbapi.INTERVAL
+
+
+class _OracleRaw(oracle.RAW):
+    pass
+
+
+class _OracleRowid(oracle.ROWID):
+    def get_dbapi_type(self, dbapi):
+        return dbapi.ROWID
+
+
+class OracleCompiler_cx_oracle(OracleCompiler):
+    _oracle_cx_sql_compiler = True
+
+    _oracle_returning = False
+
+    # Oracle bind names can't start with digits or underscores.
+    # currently we rely upon Oracle-specific quoting of bind names in most
+    # cases.  however for expanding params, the escape chars are used.
+    # see #8708
+    bindname_escape_characters = util.immutabledict(
+        {
+            "%": "P",
+            "(": "A",
+            ")": "Z",
+            ":": "C",
+            ".": "C",
+            "[": "C",
+            "]": "C",
+            " ": "C",
+            "\\": "C",
+            "/": "C",
+            "?": "C",
+        }
+    )
+
+    def bindparam_string(self, name, **kw):
+        quote = getattr(name, "quote", None)
+        if (
+            quote is True
+            or quote is not False
+            and self.preparer._bindparam_requires_quotes(name)
+            # bind param quoting for Oracle doesn't work with post_compile
+            # params.  For those, the default bindparam_string will escape
+            # special chars, and the appending of a number "_1" etc. will
+            # take care of reserved words
+            and not kw.get("post_compile", False)
+        ):
+            # interesting to note about expanding parameters - since the
+            # new parameters take the form <paramname>_<int>, at least if
+            # they are originally formed from reserved words, they no longer
+            # need quoting :).    names that include illegal characters
+            # won't work however.
+            quoted_name = '"%s"' % name
+            kw["escaped_from"] = name
+            name = quoted_name
+            return OracleCompiler.bindparam_string(self, name, **kw)
+
+        # TODO: we could likely do away with quoting altogether for
+        # Oracle parameters and use the custom escaping here
+        escaped_from = kw.get("escaped_from", None)
+        if not escaped_from:
+            if self._bind_translate_re.search(name):
+                # not quite the translate use case as we want to
+                # also get a quick boolean if we even found
+                # unusual characters in the name
+                new_name = self._bind_translate_re.sub(
+                    lambda m: self._bind_translate_chars[m.group(0)],
+                    name,
+                )
+                if new_name[0].isdigit() or new_name[0] == "_":
+                    new_name = "D" + new_name
+                kw["escaped_from"] = name
+                name = new_name
+            elif name[0].isdigit() or name[0] == "_":
+                new_name = "D" + name
+                kw["escaped_from"] = name
+                name = new_name
+
+        return OracleCompiler.bindparam_string(self, name, **kw)
+
+
+class OracleExecutionContext_cx_oracle(OracleExecutionContext):
+    out_parameters = None
+
+    def _generate_out_parameter_vars(self):
+        # check for has_out_parameters or RETURNING, create cx_Oracle.var
+        # objects if so
+        if self.compiled.has_out_parameters or self.compiled._oracle_returning:
+            out_parameters = self.out_parameters
+            assert out_parameters is not None
+
+            len_params = len(self.parameters)
+
+            quoted_bind_names = self.compiled.escaped_bind_names
+            for bindparam in self.compiled.binds.values():
+                if bindparam.isoutparam:
+                    name = self.compiled.bind_names[bindparam]
+                    type_impl = bindparam.type.dialect_impl(self.dialect)
+
+                    if hasattr(type_impl, "_cx_oracle_var"):
+                        out_parameters[name] = type_impl._cx_oracle_var(
+                            self.dialect, self.cursor, arraysize=len_params
+                        )
+                    else:
+                        dbtype = type_impl.get_dbapi_type(self.dialect.dbapi)
+
+                        cx_Oracle = self.dialect.dbapi
+
+                        assert cx_Oracle is not None
+
+                        if dbtype is None:
+                            raise exc.InvalidRequestError(
+                                "Cannot create out parameter for "
+                                "parameter "
+                                "%r - its type %r is not supported by"
+                                " cx_oracle" % (bindparam.key, bindparam.type)
+                            )
+
+                        # note this is an OUT parameter.   Using
+                        # non-LOB datavalues with large unicode-holding
+                        # values causes the failure (both cx_Oracle and
+                        # oracledb):
+                        # ORA-22835: Buffer too small for CLOB to CHAR or
+                        # BLOB to RAW conversion (actual: 16507,
+                        # maximum: 4000)
+                        # [SQL: INSERT INTO long_text (x, y, z) VALUES
+                        # (:x, :y, :z) RETURNING long_text.x, long_text.y,
+                        # long_text.z INTO :ret_0, :ret_1, :ret_2]
+                        # so even for DB_TYPE_NVARCHAR we convert to a LOB
+
+                        if isinstance(type_impl, _LOBDataType):
+                            if dbtype == cx_Oracle.DB_TYPE_NVARCHAR:
+                                dbtype = cx_Oracle.NCLOB
+                            elif dbtype == cx_Oracle.DB_TYPE_RAW:
+                                dbtype = cx_Oracle.BLOB
+                            # other LOB types go in directly
+
+                            out_parameters[name] = self.cursor.var(
+                                dbtype,
+                                # this is fine also in oracledb_async since
+                                # the driver will await the read coroutine
+                                outconverter=lambda value: value.read(),
+                                arraysize=len_params,
+                            )
+                        elif (
+                            isinstance(type_impl, _OracleNumeric)
+                            and type_impl.asdecimal
+                        ):
+                            out_parameters[name] = self.cursor.var(
+                                decimal.Decimal,
+                                arraysize=len_params,
+                            )
+
+                        else:
+                            out_parameters[name] = self.cursor.var(
+                                dbtype, arraysize=len_params
+                            )
+
+                    for param in self.parameters:
+                        param[quoted_bind_names.get(name, name)] = (
+                            out_parameters[name]
+                        )
+
+    def _generate_cursor_outputtype_handler(self):
+        output_handlers = {}
+
+        for keyname, name, objects, type_ in self.compiled._result_columns:
+            handler = type_._cached_custom_processor(
+                self.dialect,
+                "cx_oracle_outputtypehandler",
+                self._get_cx_oracle_type_handler,
+            )
+
+            if handler:
+                denormalized_name = self.dialect.denormalize_name(keyname)
+                output_handlers[denormalized_name] = handler
+
+        if output_handlers:
+            default_handler = self._dbapi_connection.outputtypehandler
+
+            def output_type_handler(
+                cursor, name, default_type, size, precision, scale
+            ):
+                if name in output_handlers:
+                    return output_handlers[name](
+                        cursor, name, default_type, size, precision, scale
+                    )
+                else:
+                    return default_handler(
+                        cursor, name, default_type, size, precision, scale
+                    )
+
+            self.cursor.outputtypehandler = output_type_handler
+
+    def _get_cx_oracle_type_handler(self, impl):
+        if hasattr(impl, "_cx_oracle_outputtypehandler"):
+            return impl._cx_oracle_outputtypehandler(self.dialect)
+        else:
+            return None
+
+    def pre_exec(self):
+        super().pre_exec()
+        if not getattr(self.compiled, "_oracle_cx_sql_compiler", False):
+            return
+
+        self.out_parameters = {}
+
+        self._generate_out_parameter_vars()
+
+        self._generate_cursor_outputtype_handler()
+
+    def post_exec(self):
+        if (
+            self.compiled
+            and is_sql_compiler(self.compiled)
+            and self.compiled._oracle_returning
+        ):
+            initial_buffer = self.fetchall_for_returning(
+                self.cursor, _internal=True
+            )
+
+            fetch_strategy = _cursor.FullyBufferedCursorFetchStrategy(
+                self.cursor,
+                [
+                    (entry.keyname, None)
+                    for entry in self.compiled._result_columns
+                ],
+                initial_buffer=initial_buffer,
+            )
+
+            self.cursor_fetch_strategy = fetch_strategy
+
+    def create_cursor(self):
+        c = self._dbapi_connection.cursor()
+        if self.dialect.arraysize:
+            c.arraysize = self.dialect.arraysize
+
+        return c
+
+    def fetchall_for_returning(self, cursor, *, _internal=False):
+        compiled = self.compiled
+        if (
+            not _internal
+            and compiled is None
+            or not is_sql_compiler(compiled)
+            or not compiled._oracle_returning
+        ):
+            raise NotImplementedError(
+                "execution context was not prepared for Oracle RETURNING"
+            )
+
+        # create a fake cursor result from the out parameters. unlike
+        # get_out_parameter_values(), the result-row handlers here will be
+        # applied at the Result level
+
+        numcols = len(self.out_parameters)
+
+        # [stmt_result for stmt_result in outparam.values] == each
+        # statement in executemany
+        # [val for val in stmt_result] == each row for a particular
+        # statement
+        return list(
+            zip(
+                *[
+                    [
+                        val
+                        for stmt_result in self.out_parameters[
+                            f"ret_{j}"
+                        ].values
+                        for val in (stmt_result or ())
+                    ]
+                    for j in range(numcols)
+                ]
+            )
+        )
+
+    def get_out_parameter_values(self, out_param_names):
+        # this method should not be called when the compiler has
+        # RETURNING as we've turned the has_out_parameters flag set to
+        # False.
+        assert not self.compiled.returning
+
+        return [
+            self.dialect._paramval(self.out_parameters[name])
+            for name in out_param_names
+        ]
+
+
+class OracleDialect_cx_oracle(OracleDialect):
+    supports_statement_cache = True
+    execution_ctx_cls = OracleExecutionContext_cx_oracle
+    statement_compiler = OracleCompiler_cx_oracle
+
+    supports_sane_rowcount = True
+    supports_sane_multi_rowcount = True
+
+    insert_executemany_returning = True
+    insert_executemany_returning_sort_by_parameter_order = True
+    update_executemany_returning = True
+    delete_executemany_returning = True
+
+    bind_typing = interfaces.BindTyping.SETINPUTSIZES
+
+    driver = "cx_oracle"
+
+    colspecs = util.update_copy(
+        OracleDialect.colspecs,
+        {
+            sqltypes.TIMESTAMP: _CXOracleTIMESTAMP,
+            sqltypes.Numeric: _OracleNumeric,
+            sqltypes.Float: _OracleNumeric,
+            oracle.BINARY_FLOAT: _OracleBINARY_FLOAT,
+            oracle.BINARY_DOUBLE: _OracleBINARY_DOUBLE,
+            sqltypes.Integer: _OracleInteger,
+            oracle.NUMBER: _OracleNUMBER,
+            sqltypes.Date: _CXOracleDate,
+            sqltypes.LargeBinary: _OracleBinary,
+            sqltypes.Boolean: oracle._OracleBoolean,
+            sqltypes.Interval: _OracleInterval,
+            oracle.INTERVAL: _OracleInterval,
+            sqltypes.Text: _OracleText,
+            sqltypes.String: _OracleString,
+            sqltypes.UnicodeText: _OracleUnicodeTextCLOB,
+            sqltypes.CHAR: _OracleChar,
+            sqltypes.NCHAR: _OracleNChar,
+            sqltypes.Enum: _OracleEnum,
+            oracle.LONG: _OracleLong,
+            oracle.RAW: _OracleRaw,
+            sqltypes.Unicode: _OracleUnicodeStringCHAR,
+            sqltypes.NVARCHAR: _OracleUnicodeStringNCHAR,
+            sqltypes.Uuid: _OracleUUID,
+            oracle.NCLOB: _OracleUnicodeTextNCLOB,
+            oracle.ROWID: _OracleRowid,
+        },
+    )
+
+    execute_sequence_format = list
+
+    _cx_oracle_threaded = None
+
+    _cursor_var_unicode_kwargs = util.immutabledict()
+
+    @util.deprecated_params(
+        threaded=(
+            "1.3",
+            "The 'threaded' parameter to the cx_oracle/oracledb dialect "
+            "is deprecated as a dialect-level argument, and will be removed "
+            "in a future release.  As of version 1.3, it defaults to False "
+            "rather than True.  The 'threaded' option can be passed to "
+            "cx_Oracle directly in the URL query string passed to "
+            ":func:`_sa.create_engine`.",
+        )
+    )
+    def __init__(
+        self,
+        auto_convert_lobs=True,
+        coerce_to_decimal=True,
+        arraysize=None,
+        encoding_errors=None,
+        threaded=None,
+        **kwargs,
+    ):
+        OracleDialect.__init__(self, **kwargs)
+        self.arraysize = arraysize
+        self.encoding_errors = encoding_errors
+        if encoding_errors:
+            self._cursor_var_unicode_kwargs = {
+                "encodingErrors": encoding_errors
+            }
+        if threaded is not None:
+            self._cx_oracle_threaded = threaded
+        self.auto_convert_lobs = auto_convert_lobs
+        self.coerce_to_decimal = coerce_to_decimal
+        if self._use_nchar_for_unicode:
+            self.colspecs = self.colspecs.copy()
+            self.colspecs[sqltypes.Unicode] = _OracleUnicodeStringNCHAR
+            self.colspecs[sqltypes.UnicodeText] = _OracleUnicodeTextNCLOB
+
+        dbapi_module = self.dbapi
+        self._load_version(dbapi_module)
+
+        if dbapi_module is not None:
+            # these constants will first be seen in SQLAlchemy datatypes
+            # coming from the get_dbapi_type() method.   We then
+            # will place the following types into setinputsizes() calls
+            # on each statement.  Oracle constants that are not in this
+            # list will not be put into setinputsizes().
+            self.include_set_input_sizes = {
+                dbapi_module.DATETIME,
+                dbapi_module.DB_TYPE_NVARCHAR,  # used for CLOB, NCLOB
+                dbapi_module.DB_TYPE_RAW,  # used for BLOB
+                dbapi_module.NCLOB,  # not currently used except for OUT param
+                dbapi_module.CLOB,  # not currently used except for OUT param
+                dbapi_module.LOB,  # not currently used
+                dbapi_module.BLOB,  # not currently used except for OUT param
+                dbapi_module.NCHAR,
+                dbapi_module.FIXED_NCHAR,
+                dbapi_module.FIXED_CHAR,
+                dbapi_module.TIMESTAMP,
+                int,  # _OracleInteger,
+                # _OracleBINARY_FLOAT, _OracleBINARY_DOUBLE,
+                dbapi_module.NATIVE_FLOAT,
+            }
+
+            self._paramval = lambda value: value.getvalue()
+
+    def _load_version(self, dbapi_module):
+        version = (0, 0, 0)
+        if dbapi_module is not None:
+            m = re.match(r"(\d+)\.(\d+)(?:\.(\d+))?", dbapi_module.version)
+            if m:
+                version = tuple(
+                    int(x) for x in m.group(1, 2, 3) if x is not None
+                )
+        self.cx_oracle_ver = version
+        if self.cx_oracle_ver < (8,) and self.cx_oracle_ver > (0, 0, 0):
+            raise exc.InvalidRequestError(
+                "cx_Oracle version 8 and above are supported"
+            )
+
+    @classmethod
+    def import_dbapi(cls):
+        import cx_Oracle
+
+        return cx_Oracle
+
+    def initialize(self, connection):
+        super().initialize(connection)
+        self._detect_decimal_char(connection)
+
+    def get_isolation_level(self, dbapi_connection):
+        # sources:
+
+        # general idea of transaction id, have to start one, etc.
+        # https://stackoverflow.com/questions/10711204/how-to-check-isoloation-level
+
+        # how to decode xid cols from v$transaction to match
+        # https://asktom.oracle.com/pls/apex/f?p=100:11:0::::P11_QUESTION_ID:9532779900346079444
+
+        # Oracle tuple comparison without using IN:
+        # https://www.sql-workbench.eu/comparison/tuple_comparison.html
+
+        with dbapi_connection.cursor() as cursor:
+            # this is the only way to ensure a transaction is started without
+            # actually running DML.   There's no way to see the configured
+            # isolation level without getting it from v$transaction which
+            # means transaction has to be started.
+            outval = cursor.var(str)
+            cursor.execute(
+                """
+                begin
+                   :trans_id := dbms_transaction.local_transaction_id( TRUE );
+                end;
+                """,
+                {"trans_id": outval},
+            )
+            trans_id = outval.getvalue()
+            xidusn, xidslot, xidsqn = trans_id.split(".", 2)
+
+            cursor.execute(
+                "SELECT CASE BITAND(t.flag, POWER(2, 28)) "
+                "WHEN 0 THEN 'READ COMMITTED' "
+                "ELSE 'SERIALIZABLE' END AS isolation_level "
+                "FROM v$transaction t WHERE "
+                "(t.xidusn, t.xidslot, t.xidsqn) = "
+                "((:xidusn, :xidslot, :xidsqn))",
+                {"xidusn": xidusn, "xidslot": xidslot, "xidsqn": xidsqn},
+            )
+            row = cursor.fetchone()
+            if row is None:
+                raise exc.InvalidRequestError(
+                    "could not retrieve isolation level"
+                )
+            result = row[0]
+
+        return result
+
+    def get_isolation_level_values(self, dbapi_connection):
+        return super().get_isolation_level_values(dbapi_connection) + [
+            "AUTOCOMMIT"
+        ]
+
+    def set_isolation_level(self, dbapi_connection, level):
+        if level == "AUTOCOMMIT":
+            dbapi_connection.autocommit = True
+        else:
+            dbapi_connection.autocommit = False
+            dbapi_connection.rollback()
+            with dbapi_connection.cursor() as cursor:
+                cursor.execute(f"ALTER SESSION SET ISOLATION_LEVEL={level}")
+
+    def _detect_decimal_char(self, connection):
+        # we have the option to change this setting upon connect,
+        # or just look at what it is upon connect and convert.
+        # to minimize the chance of interference with changes to
+        # NLS_TERRITORY or formatting behavior of the DB, we opt
+        # to just look at it
+
+        dbapi_connection = connection.connection
+
+        with dbapi_connection.cursor() as cursor:
+            # issue #8744
+            # nls_session_parameters is not available in some Oracle
+            # modes like "mount mode".  But then, v$nls_parameters is not
+            # available if the connection doesn't have SYSDBA priv.
+            #
+            # simplify the whole thing and just use the method that we were
+            # doing in the test suite already, selecting a number
+
+            def output_type_handler(
+                cursor, name, defaultType, size, precision, scale
+            ):
+                return cursor.var(
+                    self.dbapi.STRING, 255, arraysize=cursor.arraysize
+                )
+
+            cursor.outputtypehandler = output_type_handler
+            cursor.execute("SELECT 1.1 FROM DUAL")
+            value = cursor.fetchone()[0]
+
+            decimal_char = value.lstrip("0")[1]
+            assert not decimal_char[0].isdigit()
+
+        self._decimal_char = decimal_char
+
+        if self._decimal_char != ".":
+            _detect_decimal = self._detect_decimal
+            _to_decimal = self._to_decimal
+
+            self._detect_decimal = lambda value: _detect_decimal(
+                value.replace(self._decimal_char, ".")
+            )
+            self._to_decimal = lambda value: _to_decimal(
+                value.replace(self._decimal_char, ".")
+            )
+
+    def _detect_decimal(self, value):
+        if "." in value:
+            return self._to_decimal(value)
+        else:
+            return int(value)
+
+    _to_decimal = decimal.Decimal
+
+    def _generate_connection_outputtype_handler(self):
+        """establish the default outputtypehandler established at the
+        connection level.
+
+        """
+
+        dialect = self
+        cx_Oracle = dialect.dbapi
+
+        number_handler = _OracleNUMBER(
+            asdecimal=True
+        )._cx_oracle_outputtypehandler(dialect)
+        float_handler = _OracleNUMBER(
+            asdecimal=False
+        )._cx_oracle_outputtypehandler(dialect)
+
+        def output_type_handler(
+            cursor, name, default_type, size, precision, scale
+        ):
+            if (
+                default_type == cx_Oracle.NUMBER
+                and default_type is not cx_Oracle.NATIVE_FLOAT
+            ):
+                if not dialect.coerce_to_decimal:
+                    return None
+                elif precision == 0 and scale in (0, -127):
+                    # ambiguous type, this occurs when selecting
+                    # numbers from deep subqueries
+                    return cursor.var(
+                        cx_Oracle.STRING,
+                        255,
+                        outconverter=dialect._detect_decimal,
+                        arraysize=cursor.arraysize,
+                    )
+                elif precision and scale > 0:
+                    return number_handler(
+                        cursor, name, default_type, size, precision, scale
+                    )
+                else:
+                    return float_handler(
+                        cursor, name, default_type, size, precision, scale
+                    )
+
+            # if unicode options were specified, add a decoder, otherwise
+            # cx_Oracle should return Unicode
+            elif (
+                dialect._cursor_var_unicode_kwargs
+                and default_type
+                in (
+                    cx_Oracle.STRING,
+                    cx_Oracle.FIXED_CHAR,
+                )
+                and default_type is not cx_Oracle.CLOB
+                and default_type is not cx_Oracle.NCLOB
+            ):
+                return cursor.var(
+                    str,
+                    size,
+                    cursor.arraysize,
+                    **dialect._cursor_var_unicode_kwargs,
+                )
+
+            elif dialect.auto_convert_lobs and default_type in (
+                cx_Oracle.CLOB,
+                cx_Oracle.NCLOB,
+            ):
+                typ = (
+                    cx_Oracle.DB_TYPE_VARCHAR
+                    if default_type is cx_Oracle.CLOB
+                    else cx_Oracle.DB_TYPE_NVARCHAR
+                )
+                return cursor.var(
+                    typ,
+                    _CX_ORACLE_MAGIC_LOB_SIZE,
+                    cursor.arraysize,
+                    **dialect._cursor_var_unicode_kwargs,
+                )
+
+            elif dialect.auto_convert_lobs and default_type in (
+                cx_Oracle.BLOB,
+            ):
+                return cursor.var(
+                    cx_Oracle.DB_TYPE_RAW,
+                    _CX_ORACLE_MAGIC_LOB_SIZE,
+                    cursor.arraysize,
+                )
+
+        return output_type_handler
+
+    def on_connect(self):
+        output_type_handler = self._generate_connection_outputtype_handler()
+
+        def on_connect(conn):
+            conn.outputtypehandler = output_type_handler
+
+        return on_connect
+
+    def create_connect_args(self, url):
+        opts = dict(url.query)
+
+        for opt in ("use_ansi", "auto_convert_lobs"):
+            if opt in opts:
+                util.warn_deprecated(
+                    f"{self.driver} dialect option {opt!r} should only be "
+                    "passed to create_engine directly, not within the URL "
+                    "string",
+                    version="1.3",
+                )
+                util.coerce_kw_type(opts, opt, bool)
+                setattr(self, opt, opts.pop(opt))
+
+        database = url.database
+        service_name = opts.pop("service_name", None)
+        if database or service_name:
+            # if we have a database, then we have a remote host
+            port = url.port
+            if port:
+                port = int(port)
+            else:
+                port = 1521
+
+            if database and service_name:
+                raise exc.InvalidRequestError(
+                    '"service_name" option shouldn\'t '
+                    'be used with a "database" part of the url'
+                )
+            if database:
+                makedsn_kwargs = {"sid": database}
+            if service_name:
+                makedsn_kwargs = {"service_name": service_name}
+
+            dsn = self.dbapi.makedsn(url.host, port, **makedsn_kwargs)
+        else:
+            # we have a local tnsname
+            dsn = url.host
+
+        if dsn is not None:
+            opts["dsn"] = dsn
+        if url.password is not None:
+            opts["password"] = url.password
+        if url.username is not None:
+            opts["user"] = url.username
+
+        if self._cx_oracle_threaded is not None:
+            opts.setdefault("threaded", self._cx_oracle_threaded)
+
+        def convert_cx_oracle_constant(value):
+            if isinstance(value, str):
+                try:
+                    int_val = int(value)
+                except ValueError:
+                    value = value.upper()
+                    return getattr(self.dbapi, value)
+                else:
+                    return int_val
+            else:
+                return value
+
+        util.coerce_kw_type(opts, "mode", convert_cx_oracle_constant)
+        util.coerce_kw_type(opts, "threaded", bool)
+        util.coerce_kw_type(opts, "events", bool)
+        util.coerce_kw_type(opts, "purity", convert_cx_oracle_constant)
+        return ([], opts)
+
+    def _get_server_version_info(self, connection):
+        return tuple(int(x) for x in connection.connection.version.split("."))
+
+    def is_disconnect(self, e, connection, cursor):
+        (error,) = e.args
+        if isinstance(
+            e, (self.dbapi.InterfaceError, self.dbapi.DatabaseError)
+        ) and "not connected" in str(e):
+            return True
+
+        if hasattr(error, "code") and error.code in {
+            28,
+            3114,
+            3113,
+            3135,
+            1033,
+            2396,
+        }:
+            # ORA-00028: your session has been killed
+            # ORA-03114: not connected to ORACLE
+            # ORA-03113: end-of-file on communication channel
+            # ORA-03135: connection lost contact
+            # ORA-01033: ORACLE initialization or shutdown in progress
+            # ORA-02396: exceeded maximum idle time, please connect again
+            # TODO: Others ?
+            return True
+
+        if re.match(r"^(?:DPI-1010|DPI-1080|DPY-1001|DPY-4011)", str(e)):
+            # DPI-1010: not connected
+            # DPI-1080: connection was closed by ORA-3113
+            # python-oracledb's DPY-1001: not connected to database
+            # python-oracledb's DPY-4011: the database or network closed the
+            # connection
+            # TODO: others?
+            return True
+
+        return False
+
+    def create_xid(self):
+        id_ = random.randint(0, 2**128)
+        return (0x1234, "%032x" % id_, "%032x" % 9)
+
+    def do_executemany(self, cursor, statement, parameters, context=None):
+        if isinstance(parameters, tuple):
+            parameters = list(parameters)
+        cursor.executemany(statement, parameters)
+
+    def do_begin_twophase(self, connection, xid):
+        connection.connection.begin(*xid)
+        connection.connection.info["cx_oracle_xid"] = xid
+
+    def do_prepare_twophase(self, connection, xid):
+        result = connection.connection.prepare()
+        connection.info["cx_oracle_prepared"] = result
+
+    def do_rollback_twophase(
+        self, connection, xid, is_prepared=True, recover=False
+    ):
+        self.do_rollback(connection.connection)
+        # TODO: need to end XA state here
+
+    def do_commit_twophase(
+        self, connection, xid, is_prepared=True, recover=False
+    ):
+        if not is_prepared:
+            self.do_commit(connection.connection)
+        else:
+            if recover:
+                raise NotImplementedError(
+                    "2pc recovery not implemented for cx_Oracle"
+                )
+            oci_prepared = connection.info["cx_oracle_prepared"]
+            if oci_prepared:
+                self.do_commit(connection.connection)
+        # TODO: need to end XA state here
+
+    def do_set_input_sizes(self, cursor, list_of_tuples, context):
+        if self.positional:
+            # not usually used, here to support if someone is modifying
+            # the dialect to use positional style
+            cursor.setinputsizes(
+                *[dbtype for key, dbtype, sqltype in list_of_tuples]
+            )
+        else:
+            collection = (
+                (key, dbtype)
+                for key, dbtype, sqltype in list_of_tuples
+                if dbtype
+            )
+
+            cursor.setinputsizes(**{key: dbtype for key, dbtype in collection})
+
+    def do_recover_twophase(self, connection):
+        raise NotImplementedError(
+            "recover two phase query for cx_Oracle not implemented"
+        )
+
+
+dialect = OracleDialect_cx_oracle