This thread looks to be a little on the old side and therefore may no longer be relevant. Please see if there is a newer thread on the subject and ensure you're using the most recent build of any software if your question regards a particular product.
This thread has been locked and is no longer accepting new posts, if you have a question regarding this topic please email us at support@mindscape.co.nz
|
DynamicData doesn't seem to work with SimpleDB. Mindscape.LightSpeed.Linq.CountStrategy.Execute() gets a NotImplemented exception.
|
|
|
|
|
Hi Luke, Apologies for the delay in replying Luke. This is because we haven't managed to identify a COUNT() type function with SimpleDB. Are you aware of one? My hunting through the operators and queries has not resulted in finding one. We don't really want to haul all the data back and then count the rows. Appreciate your thoughts, John-Daniel |
|
|
|
|
Querying without attributes returns just the IDs which isn't too bad.
|
|
|
|
|
Hi Luke, We have now implemented Count support (using the approach of getting a list of item names) and it will be included in nightly builds dated 14 Feb 2009 and above. We have also added pseudo-paging support which is also required for Dynamic Data. I say "pseudo-paging" because SimpleDB does not support server-side paging so we have to perform the paging on the client -- e.g. if Dynamic Data asks for items 61-70 then we retrieve a full load of items and then throw the first 60, and any after the 70th, away. (We stop making new "more" requests once we have enough items, but we do not limit the size of individual requests.) Clearly this will not be efficient and will increase your data usage especially if your entity contains large fields. We would therefore advise caution when using dynamic data (or anything else that does paging or counting) with potentially large data sets! Please let us know if you run into any problems! |
|
|
|
|
Anyone using SimpleDB, whether through LightSpeed or not has to deal with this issue. I think that's a fine way of doing it. That method of paging only gets terrible if someone is paging past page 10 or so, which tends to be an unlikely scenario in most cases. For the site we're developing, we're avoiding paging on the public side and looking at using Dynamic Data for the admin, so there won't be too much paging traffic anyway. |
|
|
|
