diff --git a/psycopg/cursor_type.c b/psycopg/cursor_type.c
index d644df52..f1ed38ee 100644
--- a/psycopg/cursor_type.c
+++ b/psycopg/cursor_type.c
@@ -1267,20 +1267,23 @@ _psyco_curs_has_read_check(PyObject* o, void* var)
 static PyObject *
 psyco_curs_copy_from(cursorObject *self, PyObject *args, PyObject *kwargs)
 {
-    char *query = NULL;
-    char query_buffer[DEFAULT_COPYBUFF];
-    Py_ssize_t query_size;
-    const char *table_name;
+    static char *kwlist[] = {
+            "file", "table", "sep", "null", "size", "columns", NULL};
+
     const char *sep = "\t";
     const char *null = "\\N";
-    Py_ssize_t bufsize = DEFAULT_COPYBUFF;
-    PyObject *file, *columns = NULL, *res = NULL;
+    const char *command =
+        "COPY %s%s FROM stdin WITH DELIMITER AS %s NULL AS %s";
+
+    Py_ssize_t query_size;
+    char *query = NULL;
     char *columnlist = NULL;
     char *quoted_delimiter = NULL;
     char *quoted_null = NULL;
 
-    static char *kwlist[] = {
-            "file", "table", "sep", "null", "size", "columns", NULL};
+    const char *table_name;
+    Py_ssize_t bufsize = DEFAULT_COPYBUFF;
+    PyObject *file, *columns = NULL, *res = NULL;
 
     if (!PyArg_ParseTupleAndKeywords(args, kwargs,
         "O&s|ss" CONV_CODE_PY_SSIZE_T "O", kwlist,
@@ -1310,21 +1313,16 @@ psyco_curs_copy_from(cursorObject *self, PyObject *args, PyObject *kwargs)
         goto exit;
     }
 
-    query = query_buffer;
-    query_size = PyOS_snprintf(query, DEFAULT_COPYBUFF,
-        "COPY %s%s FROM stdin WITH DELIMITER AS %s NULL AS %s",
-        table_name, columnlist, quoted_delimiter, quoted_null);
-    if (query_size >= DEFAULT_COPYBUFF) {
-        /* Got truncated, allocate dynamically */
-        if (!(query = PyMem_New(char, query_size + 1))) {
-            PyErr_NoMemory();
-            goto exit;
-        }
-        PyOS_snprintf(query, query_size + 1,
-            "COPY %s%s FROM stdin WITH DELIMITER AS %s NULL AS %s",
-            table_name, columnlist, quoted_delimiter, quoted_null);
+    query_size = strlen(command) + strlen(table_name) + strlen(columnlist)
+        + strlen(quoted_delimiter) + strlen(quoted_null) + 1;
+    if (!(query = PyMem_New(char, query_size + 1))) {
+        PyErr_NoMemory();
+        goto exit;
     }
 
+    PyOS_snprintf(query, query_size, command,
+        table_name, columnlist, quoted_delimiter, quoted_null);
+
     Dprintf("psyco_curs_copy_from: query = %s", query);
 
     self->copysize = bufsize;
@@ -1336,14 +1334,13 @@ psyco_curs_copy_from(cursorObject *self, PyObject *args, PyObject *kwargs)
         Py_INCREF(Py_None);
     }
 
-    self->copyfile = NULL;
-    Py_DECREF(file);
+    Py_CLEAR(self->copyfile);
 
 exit:
     PyMem_Free(columnlist);
     PyMem_Free(quoted_delimiter);
     PyMem_Free(quoted_null);
-    if (query != query_buffer) { PyMem_Free(query); }
+    PyMem_Free(query);
 
     return res;
 }
@@ -1370,18 +1367,21 @@ _psyco_curs_has_write_check(PyObject* o, void* var)
 static PyObject *
 psyco_curs_copy_to(cursorObject *self, PyObject *args, PyObject *kwargs)
 {
-    char *query = NULL;
-    char query_buffer[DEFAULT_COPYBUFF];
-    size_t query_size;
-    char *columnlist = NULL;
-    const char *table_name;
+    static char *kwlist[] = {"file", "table", "sep", "null", "columns", NULL};
+
     const char *sep = "\t";
     const char *null = "\\N";
-    PyObject *file, *columns = NULL, *res = NULL;
+    const char *command =
+        "COPY %s%s TO stdout WITH DELIMITER AS %s NULL AS %s";
+
+    Py_ssize_t query_size;
+    char *query = NULL;
+    char *columnlist = NULL;
     char *quoted_delimiter = NULL;
     char *quoted_null = NULL;
 
-    static char *kwlist[] = {"file", "table", "sep", "null", "columns", NULL};
+    const char *table_name;
+    PyObject *file, *columns = NULL, *res = NULL;
 
     if (!PyArg_ParseTupleAndKeywords(args, kwargs, "O&s|ssO", kwlist,
                                      _psyco_curs_has_write_check, &file,
@@ -1409,21 +1409,16 @@ psyco_curs_copy_to(cursorObject *self, PyObject *args, PyObject *kwargs)
         goto exit;
     }
 
-    query = query_buffer;
-    query_size = PyOS_snprintf(query, DEFAULT_COPYBUFF,
-        "COPY %s%s TO stdout WITH DELIMITER AS %s NULL AS %s",
-        table_name, columnlist, quoted_delimiter, quoted_null);
-    if (query_size >= DEFAULT_COPYBUFF) {
-        /* Got truncated, allocate dynamically */
-        if (!(query = PyMem_New(char, query_size + 1))) {
-            PyErr_NoMemory();
-            goto exit;
-        }
-        PyOS_snprintf(query, query_size + 1,
-            "COPY %s%s TO stdout WITH DELIMITER AS %s NULL AS %s",
-            table_name, columnlist, quoted_delimiter, quoted_null);
+    query_size = strlen(command) + strlen(table_name) + strlen(columnlist)
+        + strlen(quoted_delimiter) + strlen(quoted_null) + 1;
+    if (!(query = PyMem_New(char, query_size))) {
+        PyErr_NoMemory();
+        goto exit;
     }
 
+    PyOS_snprintf(query, query_size, command,
+        table_name, columnlist, quoted_delimiter, quoted_null);
+
     Dprintf("psyco_curs_copy_to: query = %s", query);
 
     self->copysize = 0;
@@ -1435,14 +1430,13 @@ psyco_curs_copy_to(cursorObject *self, PyObject *args, PyObject *kwargs)
         Py_INCREF(Py_None);
     }
 
-    Py_DECREF(file);
-    self->copyfile = NULL;
+    Py_CLEAR(self->copyfile);
 
 exit:
     PyMem_Free(columnlist);
     PyMem_Free(quoted_delimiter);
     PyMem_Free(quoted_null);
-    if (query != query_buffer) { PyMem_Free(query); }
+    PyMem_Free(query);
 
     return res;
 }
@@ -1510,8 +1504,7 @@ psyco_curs_copy_expert(cursorObject *self, PyObject *args, PyObject *kwargs)
         Py_INCREF(res);
     }
 
-    self->copyfile = NULL;
-    Py_DECREF(file);
+    Py_CLEAR(self->copyfile);
 
 exit:
     Py_XDECREF(sql);