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Added support with cursors without scroll clause

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Using nothing is different from NO SCROLL, see DECLARE notes
in PG docs.
This commit is contained in:
Daniele Varrazzo 2012-08-15 09:44:44 +01:00
parent d074b096be
commit a79a5292e7
4 changed files with 104 additions and 44 deletions
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53
psycopg/connection_type.c
View File

@ -52,75 +52,70 @@
static PyObject *
psyco_conn_cursor(connectionObject *self, PyObject *args, PyObject *kwargs)
{
PyObject *obj;
PyObject *obj = NULL;
PyObject *rv = NULL;
PyObject *name = Py_None;
PyObject *factory = (PyObject *)&cursorType;
PyObject *withhold = Py_False;
PyObject *scrollable = Py_False;
PyObject *scrollable = Py_None;
static char *kwlist[] = {
"name", "cursor_factory", "withhold", "scrollable", NULL};
EXC_IF_CONN_CLOSED(self);
if (!PyArg_ParseTupleAndKeywords(
args, kwargs, "|OOOO", kwlist,
&name, &factory, &withhold, &scrollable)) {
return NULL;
goto exit;
}
if (PyObject_IsTrue(withhold) && (name == Py_None)) {
PyErr_SetString(ProgrammingError,
"'withhold=True can be specified only for named cursors");
return NULL;
}
if (PyObject_IsTrue(scrollable) && (name == Py_None)) {
PyErr_SetString(ProgrammingError,
"'scrollable=True can be specified only for named cursors");
return NULL;
}
EXC_IF_CONN_CLOSED(self);
if (self->status != CONN_STATUS_READY &&
self->status != CONN_STATUS_BEGIN &&
self->status != CONN_STATUS_PREPARED) {
PyErr_SetString(OperationalError,
"asynchronous connection attempt underway");
return NULL;
goto exit;
}
if (name != Py_None && self->async == 1) {
PyErr_SetString(ProgrammingError,
"asynchronous connections "
"cannot produce named cursors");
return NULL;
goto exit;
}
Dprintf("psyco_conn_cursor: new %s cursor for connection at %p",
(name == Py_None ? "unnamed" : "named"), self);
if (!(obj = PyObject_CallFunctionObjArgs(factory, self, name, NULL))) {
return NULL;
goto exit;
}
if (PyObject_IsInstance(obj, (PyObject *)&cursorType) == 0) {
PyErr_SetString(PyExc_TypeError,
"cursor factory must be subclass of psycopg2._psycopg.cursor");
Py_DECREF(obj);
return NULL;
goto exit;
}
if (PyObject_IsTrue(withhold))
((cursorObject*)obj)->withhold = 1;
if (PyObject_IsTrue(scrollable))
((cursorObject*)obj)->scrollable = 1;
if (0 != psyco_curs_withhold_set((cursorObject *)obj, withhold)) {
goto exit;
}
if (0 != psyco_curs_scrollable_set((cursorObject *)obj, scrollable)) {
goto exit;
}
Dprintf("psyco_conn_cursor: new cursor at %p: refcnt = "
FORMAT_CODE_PY_SSIZE_T,
obj, Py_REFCNT(obj)
);
return obj;
);
rv = obj;
obj = NULL;
exit:
Py_XDECREF(obj);
return rv;
}

10
psycopg/cursor.h
View File

@ -43,7 +43,11 @@ struct cursorObject {
int closed:1; /* 1 if the cursor is closed */
int notuples:1; /* 1 if the command was not a SELECT query */
int withhold:1; /* 1 if the cursor is named and uses WITH HOLD */
int scrollable:1; /* 1 if the cursor is named as SCROLLABLE */
int scrollable; /* 1 if the cursor is named and SCROLLABLE,
0 if not scrollable
-1 if undefined (PG may decide scrollable or not)
*/
long int rowcount; /* number of rows affected by last execute */
long int columns; /* number of columns fetched from the db */
@ -85,9 +89,11 @@ struct cursorObject {
};
/* C-callable functions in cursor_int.c and cursor_ext.c */
/* C-callable functions in cursor_int.c and cursor_type.c */
BORROWED HIDDEN PyObject *curs_get_cast(cursorObject *self, PyObject *oid);
HIDDEN void curs_reset(cursorObject *self);
HIDDEN int psyco_curs_withhold_set(cursorObject *self, PyObject *pyvalue);
HIDDEN int psyco_curs_scrollable_set(cursorObject *self, PyObject *pyvalue);
/* exception-raising macros */
#define EXC_IF_CURS_CLOSED(self) \

57
psycopg/cursor_type.c
View File

@ -370,6 +370,7 @@ _psyco_curs_execute(cursorObject *self,
int res = -1;
int tmp;
PyObject *fquery, *cvt = NULL;
const char *scroll;
operation = _psyco_curs_validate_sql_basic(self, operation);
@ -396,6 +397,21 @@ _psyco_curs_execute(cursorObject *self,
if (0 > _mogrify(vars, operation, self, &cvt)) { goto exit; }
}
switch (self->scrollable) {
case -1:
scroll = "";
break;
case 0:
scroll = "NO SCROLL ";
break;
case 1:
scroll = "SCROLL ";
break;
default:
PyErr_SetString(InternalError, "unexpected scrollable value");
goto exit;
}
if (vars && cvt) {
if (!(fquery = _psyco_curs_merge_query_args(self, operation, cvt))) {
goto exit;
@ -403,9 +419,9 @@ _psyco_curs_execute(cursorObject *self,
if (self->name != NULL) {
self->query = Bytes_FromFormat(
"DECLARE \"%s\" %sSCROLL CURSOR %s HOLD FOR %s",
"DECLARE \"%s\" %sCURSOR %s HOLD FOR %s",
self->name,
self->scrollable ? "":"NO ",
scroll,
self->withhold ? "WITH" : "WITHOUT",
Bytes_AS_STRING(fquery));
Py_DECREF(fquery);
@ -417,9 +433,9 @@ _psyco_curs_execute(cursorObject *self,
else {
if (self->name != NULL) {
self->query = Bytes_FromFormat(
"DECLARE \"%s\" %sSCROLL CURSOR %s HOLD FOR %s",
"DECLARE \"%s\" %sCURSOR %s HOLD FOR %s",
self->name,
self->scrollable ? "":"NO ",
scroll,
self->withhold ? "WITH" : "WITHOUT",
Bytes_AS_STRING(operation));
}
@ -1567,12 +1583,12 @@ psyco_curs_withhold_get(cursorObject *self)
return ret;
}
static int
int
psyco_curs_withhold_set(cursorObject *self, PyObject *pyvalue)
{
int value;
if (self->name == NULL) {
if (pyvalue != Py_False && self->name == NULL) {
PyErr_SetString(ProgrammingError,
"trying to set .withhold on unnamed cursor");
return -1;
@ -1592,25 +1608,42 @@ psyco_curs_withhold_set(cursorObject *self, PyObject *pyvalue)
static PyObject *
psyco_curs_scrollable_get(cursorObject *self)
{
PyObject *ret;
ret = self->scrollable ? Py_True : Py_False;
Py_INCREF(ret);
PyObject *ret = NULL;
switch (self->scrollable) {
case -1:
ret = Py_None;
break;
case 0:
ret = Py_False;
break;
case 1:
ret = Py_True;
break;
default:
PyErr_SetString(InternalError, "unexpected scrollable value");
}
Py_XINCREF(ret);
return ret;
}
static int
int
psyco_curs_scrollable_set(cursorObject *self, PyObject *pyvalue)
{
int value;
if (self->name == NULL) {
if (pyvalue != Py_None && self->name == NULL) {
PyErr_SetString(ProgrammingError,
"trying to set .scrollable on unnamed cursor");
return -1;
}
if ((value = PyObject_IsTrue(pyvalue)) == -1)
if (pyvalue == Py_None) {
value = -1;
} else if ((value = PyObject_IsTrue(pyvalue)) == -1) {
return -1;
}
self->scrollable = value;

28
tests/test_cursor.py
View File

@ -226,7 +226,7 @@ class CursorTests(unittest.TestCase):
for t in range(2):
if not t:
curs = self.conn.cursor("S")
self.assertEqual(curs.scrollable, False);
self.assertEqual(curs.scrollable, None);
curs.scrollable = True
else:
curs = self.conn.cursor("S", scrollable=True)
@ -252,6 +252,32 @@ class CursorTests(unittest.TestCase):
curs.close()
def test_not_scrollable(self):
self.assertRaises(psycopg2.ProgrammingError, self.conn.cursor,
scrollable=False)
curs = self.conn.cursor()
curs.execute("create table scrollable (data int)")
curs.executemany("insert into scrollable values (%s)",
[ (i,) for i in range(100) ])
curs.close()
curs = self.conn.cursor("S") # default scrollability
curs.execute("select * from scrollable")
self.assertEqual(curs.scrollable, None)
curs.scroll(2)
try:
curs.scroll(-1)
except psycopg2.OperationalError:
return self.skipTest("can't evaluate non-scrollable cursor")
curs.close()
curs = self.conn.cursor("S", scrollable=False)
self.assertEqual(curs.scrollable, False)
curs.execute("select * from scrollable")
curs.scroll(2)
self.assertRaises(psycopg2.OperationalError, curs.scroll, -1)
@skip_before_postgres(8, 2)
def test_iter_named_cursor_efficient(self):
curs = self.conn.cursor('tmp')