Hi, I should be able to look at this one in a few days when I return and resume work (I am currently on a vacation till 5th Nov).
However, the exception suggests that building the secondary feed pipeline encountered an exception. Can you share the logs so that I can get a better understanding of the sequence of steps that happened as your statement executed. I have intermittent access to net, but should be able to revert with some delays. On Nov 2, 2015 2:32 AM, "Jianfeng Jia" <[email protected]> wrote: > I’ve tried the “apply AQLfunction” idea, but got an NullPointException: > java.lang.NullPointerException > at > org.apache.asterix.aql.translator.AqlTranslator.getFeedJointKey(AqlTranslator.java:2268) > at > org.apache.asterix.aql.translator.AqlTranslator.getFeedConnectionRequest(AqlTranslator.java:2214) > at > org.apache.asterix.aql.translator.AqlTranslator.handleConnectFeedStatement(AqlTranslator.java:2130) > at > org.apache.asterix.aql.translator.AqlTranslator.compileAndExecute(AqlTranslator.java:362) > at > org.apache.asterix.api.http.servlet.APIServlet.doPost(APIServlet.java:114) > at javax.servlet.http.HttpServlet.service(HttpServlet.java:754) > at javax.servlet.http.HttpServlet.service(HttpServlet.java:847) > at > org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:546) > at > org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:483) > at > org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:231) > at > org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:970) > at > org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:411) > at > org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:192) > at > org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:904) > at > org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:117) > at > org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:110) > at org.eclipse.jetty.server.Server.handle(Server.java:347) > at > org.eclipse.jetty.server.HttpConnection.handleRequest(HttpConnection.java:439) > at > org.eclipse.jetty.server.HttpConnection$RequestHandler.content(HttpConnection.java:924) > at org.eclipse.jetty.http.HttpParser.parseNext(HttpParser.java:781) > at > org.eclipse.jetty.http.HttpParser.parseAvailable(HttpParser.java:220) > at > org.eclipse.jetty.server.AsyncHttpConnection.handle(AsyncHttpConnection.java:43) > at > org.eclipse.jetty.io.nio.SelectChannelEndPoint.handle(SelectChannelEndPoint.java:545) > at > org.eclipse.jetty.io.nio.SelectChannelEndPoint$1.run(SelectChannelEndPoint.java:43) > at > org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:529) > at java.lang.Thread.run(Thread.java:745) > > The ddl that I was using is here: > https://gist.githubusercontent.com/JavierJia/ca596df82ffdd456001f/raw/ea86f9ad1531a68c3ecf9036ef5b69976893149d/feed-ddl.aql > < > https://gist.githubusercontent.com/JavierJia/ca596df82ffdd456001f/raw/ea86f9ad1531a68c3ecf9036ef5b69976893149d/feed-ddl.aql > > > Anyone has any idea? Thank you! > > > On Oct 30, 2015, at 12:30 AM, Heri Ramampiaro <[email protected]> wrote: > > > > Although I haven’t tested this (I have mostly used & created java-based > UDFs), > > one can execute AQL calls from within a UDF. Feeds allows functions to > > execute arbitrary AQL statements (DDL, DMLs etc). I.e., I believe what > > you are trying to do is possible. > > > > For example you could do: > > (Given that you have a rec. type called Tweet, and a dataset > ProcessedTweets > > > > create feed CoordTwitterFeed if not exists > > using “push_twitter" (("type-name"="Tweet”)) > > apply function find-intersection; > > > > (Here "find-intersection” is an AQL function that does the step > specified under 2)). > > > > To do nr. 3 the easiest way is to have a modified version of the > “hashTag” > > (let’s call this “tweetlocator”). Java-based UDF (see my previous > message with the > > TweetLib example). You can then connect this as a secondary feed, > connected to > > “CoordTwitterFeed”. > > > > E.g.: > > create secondary feed ProcessedTwitterFeed from feed CoordTwitterFeed > > apply function “tweelib#tweetlocator"; > > > > Thereafter you can connect the feeds to appropriate datasets. > > > > (Since the find-intersection is an AQL function, you can also call > “tweelib#tweetlocator” > > inside this function). > > > > Best, > > -heri > > > >> On Oct 30, 2015, at 12:18 AM, Young-Seok Kim <[email protected]> wrote: > >> > >> I'm not sure whether the following UDF is possible or not, but > hopefully it > >> is. > >> What we're trying to do is to have the following UDF. > >> > >> The UDF > >> 1) accepts an incoming tweet record through a feed job as an input and > then > >> 2) takes a field, more specifically, coordinate field value from the > tweet > >> record and sends a spatial-intersect query using the coordinate in > order to > >> find out the corresponding county of the coordinates (we have created > >> AsterixDB instance which stores US county shapes records into a dataset > and > >> created R-tree index on the polygon field of it, so the query will > return > >> the county effectively using the R-tree index) > >> 3) creates a new tweet record consisting of the original record's > fields + > >> the returned county value > >> 4) ingests to a tweet dataset in the AsterixDB instance. > >> > >> Can we have such an UDF? > >> > >> Best, > >> Young-Seok > >> > >> > >> On Thu, Oct 29, 2015 at 3:53 PM, Heri Ramampiaro <[email protected]> > wrote: > >> > >>>> > >>>> 2. Can we use AQL function in those kind of feed UDFs? > >>> > >>> Can you give an example of what you are trying to do? > >>> I.e do you want to run an AQL inside a UDF or use an AQL function as a > >>> UDF connected to a running feed? > >>> > >>> -heri > > > > > > Best, > > Jianfeng Jia > PhD Candidate of Computer Science > University of California, Irvine > >
