[TD251]fix python connector to process NCHAR

src/connector/python/linux/python2/taos/cinterface.py

@@ -96,7 +96,8 @@ def _crow_nchar_to_python(data, num_of_rows, nbytes=None, micro=False):
     for i in range(abs(num_of_rows)):
         try:
             if num_of_rows >= 0:
-                res.append( (ctypes.cast(data+nbytes*(abs(num_of_rows - i -1)),  ctypes.POINTER(ctypes.c_char * (nbytes//4))))[0].value )
+                tmpstr = ctypes.c_char_p(data)
+                res.append( tmpstr.value.decode() )
             else:
                 res.append( (ctypes.cast(data+nbytes*i,  ctypes.POINTER(ctypes.c_wchar * (nbytes//4))))[0].value )
         except ValueError:

src/connector/python/linux/python3/taos/cinterface.py

@@ -96,7 +96,8 @@ def _crow_nchar_to_python(data, num_of_rows, nbytes=None, micro=False):
     for i in range(abs(num_of_rows)):
         try:
             if num_of_rows >= 0:
-                res.append( (ctypes.cast(data+nbytes*(abs(num_of_rows - i -1)),  ctypes.POINTER(ctypes.c_char * (nbytes//4))))[0].value )
+                tmpstr = ctypes.c_char_p(data)
+                res.append( tmpstr.value.decode() )
             else:
                 res.append( (ctypes.cast(data+nbytes*i,  ctypes.POINTER(ctypes.c_wchar * (nbytes//4))))[0].value )
         except ValueError:

src/connector/python/windows/python2/taos/cinterface.py

@@ -96,7 +96,8 @@ def _crow_nchar_to_python(data, num_of_rows, nbytes=None, micro=False):
     for i in range(abs(num_of_rows)):
         try:
             if num_of_rows >= 0:
-                res.append( (ctypes.cast(data+nbytes*(abs(num_of_rows - i -1)),  ctypes.POINTER(ctypes.c_char * (nbytes//4))))[0].value )
+                tmpstr = ctypes.c_char_p(data)
+                res.append( tmpstr.value.decode() )
             else:
                 res.append( (ctypes.cast(data+nbytes*i,  ctypes.POINTER(ctypes.c_wchar * (nbytes//4))))[0].value )
         except ValueError:

src/connector/python/windows/python3/taos/cinterface.py

@@ -96,7 +96,8 @@ def _crow_nchar_to_python(data, num_of_rows, nbytes=None, micro=False):
     for i in range(abs(num_of_rows)):
         try:
             if num_of_rows >= 0:
-                res.append( (ctypes.cast(data+nbytes*(abs(num_of_rows - i -1)),  ctypes.POINTER(ctypes.c_char * (nbytes//4))))[0].value )
+                tmpstr = ctypes.c_char_p(data)
+                res.append( tmpstr.value.decode() )
             else:
                 res.append( (ctypes.cast(data+nbytes*i,  ctypes.POINTER(ctypes.c_wchar * (nbytes//4))))[0].value )
         except ValueError: