Internal change to slightly improve performance of LOB reads and writes.

Author: anthony-tuininga

doc/src/release_notes.rst

@@ -24,6 +24,7 @@ Thin Mode Changes
 #)  Fixed bug when fetch variables contain output converters and a query is
     re-executed
     (`issue 271 <https://github.com/oracle/python-oracledb/issues/271>`__).
+#)  Internal change to slightly improve performance of LOB reads and writes.
 
 Common Changes
 ++++++++++++++

src/oracledb/impl/thin/constants.pxi

@@ -1,5 +1,5 @@
 #------------------------------------------------------------------------------
-# Copyright (c) 2020, 2023, Oracle and/or its affiliates.
+# Copyright (c) 2020, 2024, Oracle and/or its affiliates.
 #
 # This software is dual-licensed to you under the Universal Permissive License
 # (UPL) 1.0 as shown at https://oss.oracle.com/licenses/upl and Apache License
@@ -676,8 +676,8 @@ cdef enum:
     TNS_ENCODING_CONV_LENGTH = 0x02
 
 # character set strings
-cdef str TNS_ENCODING_UTF8 = "UTF-8"
-cdef str TNS_ENCODING_UTF16 = "UTF-16BE"
+cdef const char* TNS_ENCODING_UTF8 = "UTF-8"
+cdef const char* TNS_ENCODING_UTF16 = "UTF-16BE"
 
 # compile time capability indices
 cdef enum:

src/oracledb/impl/thin/lob.pyx

@@ -1,5 +1,5 @@
 #------------------------------------------------------------------------------
-# Copyright (c) 2020, 2022, Oracle and/or its affiliates.
+# Copyright (c) 2020, 2024, Oracle and/or its affiliates.
 #
 # This software is dual-licensed to you under the Universal Permissive License
 # (UPL) 1.0 as shown at https://oss.oracle.com/licenses/upl and Apache License
@@ -152,10 +152,10 @@ cdef class BaseThinLobImpl(BaseLobImpl):
                 raise TypeError(
                     "only strings can be written to CLOBs and NCLOBS"
                 )
-            message.data = value.encode(self._get_encoding())
+            message.data = (<str> value).encode(self._get_encoding())
         return message
 
-    cdef str _get_encoding(self):
+    cdef const char* _get_encoding(self):
         """
         Return the encoding used by the LOB.
         """

src/oracledb/impl/thin/messages.pyx

@@ -2208,9 +2208,9 @@ cdef class LobOpMessage(Message):
     cdef int _process_message(self, ReadBuffer buf,
                               uint8_t message_type) except -1:
         cdef:
+            const char* encoding
             const char_type *ptr
             ssize_t num_bytes
-            str encoding
         if message_type == TNS_MSG_TYPE_LOB_DATA:
             buf.read_raw_bytes_and_length(&ptr, &num_bytes)
             if self.source_lob_impl.dbtype._ora_type_num == TNS_DATA_TYPE_BLOB: