Hello, Thanks for the help. I'll perform the request in 2 steps to achieve the results.
On 30 nov, 04:09, monotasker <[email protected]> wrote: > When I've done date-related operations I've had to use the python datetime > and calendar modules. They're both in the standard library so you can just > do "import datetime, calendar" at the top of your model or controller. Then > you could do a simple query for all the transactions on that budget in a > particular month. As a second step you could then use these python modules > to determine which row object has the latest date or datetime field. > > If you haven't worked with the datetime module much before it's a bit > counter-intuitive at first, but it's powerful. The key is that time *spans* > have to be represented with a datetime.timedelta() object. You can subtract > one datetime object from another using arithmetic operators, but the result > is a .timedelta(). One way to figure out the latest in a series of dates, > then, would be something like this (untested code that might be full of > syntax errors!!!): > > #assume you've made a dict of datetimes and id's from the rows returned by > your db query -- let's call it "dateset". > > nowtime = datetime.datetime.utcnow() > latest = {} > for i,d in datelist.items(): > if (nowtime - d) > latest: > pass > else: > latest = {i:d} > return latest > > The dict returned should provide you with the latest datetime (i.e., the > one closest to now) from your query results, along with the id of the row > holding that date. You can then filter your original query to retrieve just > that row. > > #it's a good idea to use .utcnow() instead of the simple .now() to avoid > any timezone issues
