Fixed bug with ordering of binds in SQL when the database version is

12.1 (#135).

Author: anthony-tuininga

doc/src/release_notes.rst

@@ -33,6 +33,8 @@ Thin Mode Changes
 #)  Fixed bug with SQL containing multibyte characters with certain database
     character sets
     (`issue 133 <https://github.com/oracle/python-oracledb/issues/133>`__).
+#)  Fixed bug with ordering of binds in SQL when the database version is 12.1
+    (`issue 135 <https://github.com/oracle/python-oracledb/issues/135>`__).
 #)  Fixed bug with ordering of binds in PL/SQL when the bind variable may
     potentially exceed the 32767 byte limit but the actual value bound does not
     (`issue 146 <https://github.com/oracle/python-oracledb/issues/146>`__).

src/oracledb/impl/thin/buffer.pyx

@@ -267,7 +267,8 @@ cdef class Buffer:
         cdef ssize_t chunk_len
         if num_bytes <= TNS_MAX_SHORT_LENGTH:
             self.write_uint8(<uint8_t> num_bytes)
-            self.write_raw(ptr, num_bytes)
+            if num_bytes > 0:
+                self.write_raw(ptr, num_bytes)
         else:
             self.write_uint8(TNS_LONG_LENGTH_INDICATOR)
             while num_bytes > 0:

src/oracledb/impl/thin/capabilities.pyx

@@ -38,6 +38,7 @@ cdef class Capabilities:
         uint16_t ncharset_id
         bytearray compile_caps
         bytearray runtime_caps
+        uint32_t max_string_size
         bint supports_oob
 
     def __init__(self):
@@ -57,7 +58,10 @@ cdef class Capabilities:
 
     @cython.boundscheck(False)
     cdef void _adjust_for_server_runtime_caps(self, bytearray server_caps):
-        pass
+        if server_caps[TNS_RCAP_TTC] & TNS_RCAP_TTC_32K:
+            self.max_string_size = 32767
+        else:
+            self.max_string_size = 4000
 
     cdef int _check_ncharset_id(self) except -1:
         """

src/oracledb/impl/thin/constants.pxi

@@ -716,7 +716,6 @@ DEF TNS_MAX_ROWID_LENGTH = 18
 DEF TNS_DURATION_MID = 0x80000000
 DEF TNS_DURATION_OFFSET = 60
 DEF TNS_DURATION_SESSION = 10
-DEF TNS_MIN_LONG_LENGTH = 0x8000
 DEF TNS_MAX_LONG_LENGTH = 0x7fffffff
 DEF TNS_SDU = 8192
 DEF TNS_TDU = 65535

src/oracledb/impl/thin/messages.pyx

@@ -934,7 +934,7 @@ cdef class MessageWithData(Message):
             # expects that and complains if any other value is sent!
             buf.write_uint8(0)
             buf.write_uint8(0)
-            if buffer_size >= TNS_MIN_LONG_LENGTH:
+            if buffer_size > buf._caps.max_string_size:
                 buf.write_ub4(TNS_MAX_LONG_LENGTH)
             else:
                 buf.write_ub4(buffer_size)
@@ -1062,7 +1062,7 @@ cdef class MessageWithData(Message):
                     self._write_bind_params_column(buf, var_impl, value)
             else:
                 if not self.cursor_impl._statement._is_plsql \
-                        and var_impl.buffer_size >= TNS_MIN_LONG_LENGTH:
+                        and var_impl.buffer_size > buf._caps.max_string_size:
                     found_long = True
                     continue
                 self._write_bind_params_column(buf, var_impl,
@@ -1072,7 +1072,7 @@ cdef class MessageWithData(Message):
                 if bind_info._is_return_bind:
                     continue
                 var_impl = bind_info._bind_var_impl
-                if var_impl.buffer_size < TNS_MIN_LONG_LENGTH:
+                if var_impl.buffer_size <= buf._caps.max_string_size:
                     continue
                 self._write_bind_params_column(buf, var_impl,
                                                var_impl._values[pos + offset])