Live Framework DataEntry Query $filter startswith does not work with Type field

Question

I have found a potential bug and need some validation or a work around.

i have a LINQ query that looks like:

                    var tagEntries = (from te in mc.TagsDF.CreateQuery<DataEntry>()
                                      where te.Resource.Type.StartsWith(type)
                                      select te);

This is generating a URL like:

https://user-ctp.windows.net/V0.1/Mesh/MeshObjects/<MeshObjectID>/DataFeeds/<DataFeedID>/Entries/?$filter=startswith(Type,'Tag')

Problem: This query does not work.  Same behavior executing directly from the LiveFX Browser...

However, the following query with Title instead of Type will work:

https://user-ctp.windows.net/V0.1/Mesh/MeshObjects/<MeshObjectID>/DataFeeds/<DataFeedID>/Entries/?$filter=startswith(Title,'Tag')

There is very little documentation on $filter limitations--only a small list of examples, of which startswith(Type,'value') is excluded.

Please advise asap.

Answer 1

Update

It appears my problem is currently isolated to a particular DataFeed.  I have tested the $filter=startswith(Type,'Tag') function on other DataFeeds with success.  However, on the feed i need it to work on, i'm receiving the following error:

{
    "Title" : "ErrorResource",
    "Code" : 410,
    "Message" : "An error has occurred."
}

Cause of Problem

After more investigation, I have determined the cause of this problem--these functions break if there are DataEntries without a Type field or Type == null.  In summary:

- You CANNOT use the startswith() or contains() filters if the DataFeed contains a DataEntry where the field referenced in the function (in this case Type) == null.  I presume this applies to other fields; however, i haven't confirmed it--i know it's the case with Type.

- The operators, such as eq and ne work fine on null fields.  Only the partial match functions startswith, contains, etc. will fail.


Work Around

THIS IS A BUG from my perspective.  I would like the LiveFX team to validate that or explain why if this is as it was intended.

If you use any of the partial match functions, then the work-around is simply to ensure no DataEntries have null values for that field.  In my case, once all of my DataEntries had a value for Type, the partial match functions work.

Answer 2

Hello, thanks for reporting this issue. I can reproduce it on my side. Can you please submit a feedback on https://connect.microsoft.com/site/sitehome.aspx?SiteID=630?

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Lante, shanaolanxing This posting is provided "AS IS" with no warranties, and confers no rights.

Answer 3

Thanks shwan for reporting this, please go ahead and log a bug at following link:

https://connect.microsoft.com/liveframework/feedback?wa=wsignin1.0

thanks a lot!

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This posting is provided "AS IS" with no warranties, and confers no rights.

Answer 4

Bug has been submitted:

https://connect.microsoft.com/liveframework/feedback/ViewFeedback.aspx?FeedbackID=473353

It would be very helpful if you could address a related issue:

http://social.msdn.microsoft.com/Forums/en-US/liveframework/thread/0fdc319f-296d-4aa6-a6a0-00c397af94e4

Thanks, -Shawn.