HD Mail wrote:
Actually, ignore my last post. I had a closer look and created this
patch. Hopefully it can be of some use.
I added a for_update attribute to the Select class.
Then changed the ansisql.py:
def visit_select_postclauses
to add my for_update statement.
It seems to work for me.
Huy
Michael Bayer wrote:
I dont have "FOR UPDATE" in there as of yet. it can be added easily
enough, although im short on time this week. feel free to add a
ticket (or dig around sql.py and see if you can figure it out)
Thanks Michael. I did have a look. I could add it in SelectBaseMixin
the same way you do order_by/group_by but because I not too familiar
with SA internals, I'm a bit reluctant.
Huy
On Mar 29, 2006, at 8:00 AM, HD Mail wrote:
Hi,
I am building a select using
st = table.select()
st.append_whereclause(...)
Is it possible to append something like "FOR UPDATE" at the end of
the generated select statement.
Before anyone shoots me down for using "for update", i'm writing a
stock control system.
I love the query building features in SA so I really want to use it
to write my sql rather then using straight sql.
Thanks
Huy
-------------------------------------------------------
This SF.Net email is sponsored by xPML, a groundbreaking scripting
language
that extends applications into web and mobile media. Attend the live
webcast
and join the prime developer group breaking into this new coding
territory!
http://sel.as-us.falkag.net/sel?cmd=lnk&kid=110944&bid=241720&dat=121642
_______________________________________________
Sqlalchemy-users mailing list
Sqlalchemy-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/sqlalchemy-users
-------------------------------------------------------
This SF.Net email is sponsored by xPML, a groundbreaking scripting
language
that extends applications into web and mobile media. Attend the live
webcast
and join the prime developer group breaking into this new coding
territory!
http://sel.as-us.falkag.net/sel?cmd=lnk&kid=110944&bid=241720&dat=121642
_______________________________________________
Sqlalchemy-users mailing list
Sqlalchemy-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/sqlalchemy-users
-------------------------------------------------------
This SF.Net email is sponsored by xPML, a groundbreaking scripting
language
that extends applications into web and mobile media. Attend the live
webcast
and join the prime developer group breaking into this new coding
territory!
http://sel.as-us.falkag.net/sel?cmd=lnk&kid=110944&bid=241720&dat=121642
_______________________________________________
Sqlalchemy-users mailing list
Sqlalchemy-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/sqlalchemy-users
Index: ansisql.py
===================================================================
--- ansisql.py (revision 1144)
+++ ansisql.py (working copy)
@@ -379,7 +379,9 @@
def visit_select_postclauses(self, select):
""" called when building a SELECT statement, position is after all
other SELECT clauses. Most DB syntaxes put LIMIT/OFFSET here """
- return (select.limit or select.offset) and self.limit_clause(select)
or ""
+ limit_sql = (select.limit or select.offset) and
self.limit_clause(select) or ""
+ for_update_sql = select.for_update and self.for_update_clause(select)
or ""
+ return ' '.join([limit_sql, for_update_sql])
def limit_clause(self, select):
if select.limit is not None:
@@ -389,6 +391,12 @@
return " \n LIMIT -1"
return " OFFSET " + str(select.offset)
+ def for_update_clause(self, select):
+ if select.for_update:
+ return " \n FOR UPDATE"
+ else:
+ return ""
+
def visit_table(self, table):
self.froms[table] = table.fullname
self.strings[table] = ""
Index: sql.py
===================================================================
--- sql.py (revision 1144)
+++ sql.py (working copy)
@@ -1126,6 +1126,7 @@
self._append_clause('order_by_clause', "ORDER BY", *clauses)
def group_by(self, *clauses):
self._append_clause('group_by_clause', "GROUP BY", *clauses)
+
def _append_clause(self, attribute, prefix, *clauses):
if len(clauses) == 1 and clauses[0] is None:
try:
@@ -1199,7 +1200,7 @@
class Select(SelectBaseMixin, FromClause):
"""represents a SELECT statement, with appendable clauses, as well as
the ability to execute itself and return a result set."""
- def __init__(self, columns=None, whereclause = None, from_obj = [],
order_by = None, group_by=None, having=None, use_labels = False,
distinct=False, engine = None, limit=None, offset=None, scalar=False,
correlate=True):
+ def __init__(self, columns=None, whereclause = None, from_obj = [],
order_by = None, group_by=None, having=None, use_labels = False,
distinct=False, engine = None, limit=None, offset=None, scalar=False,
correlate=True, for_update=False):
self._froms = util.OrderedDict()
self.use_labels = use_labels
self.id = "Select(%d)" % id(self)
@@ -1210,6 +1211,7 @@
self.oid_column = None
self.limit = limit
self.offset = offset
+ self.for_update = for_update
# indicates that this select statement should not expand its columns
# into the column clause of an enclosing select, and should instead
