8 Replies Latest reply on Jun 4, 2019 8:25 AM by Gianni Ceresa

    Restarting PGX server using start_server is throwing exception

    mohanr.k
    mohanr.k Feb 21, 2019 10:14 PM

      I configured pgx.conf file to load graph data from property graph tables and started it. Looks like it started properly because I didn't see any errors on console window.

       

      Now I realized I missed vertex loading property (use_vertex_property_value_as_label) in graph config file so I killed the server by pressing Ctrl+C and then made the required changes to graph config file. I am seeing below exception when I restart the server after this change.

       

      16:55:14.051 [main] ERROR oracle.pgx.rest.PgxContextListener - java.lang.IllegalArgumentException: java.util.concurrent.ExecutionException: oracle.pgx.common.ParallelExecutionException: java.lang.IllegalArgumentException: Adding a string for earlier idx.

      java.util.concurrent.ExecutionException: java.lang.IllegalArgumentException: java.util.concurrent.ExecutionException: oracle.pgx.common.ParallelExecutionException: java.lang.IllegalArgumentException: Adding a string for earlier idx.

      at java.util.concurrent.CompletableFuture.reportGet(Unknown Source) ~[?:1.8.0_201]

      at java.util.concurrent.CompletableFuture.get(Unknown Source) ~[?:1.8.0_201]

      at oracle.pgx.api.PgxFuture.get(PgxFuture.java:99) ~[pgx-api-3.1.0.jar:3.1.0]

      at oracle.pgx.api.ServerInstance.startEngine(ServerInstance.java:848) ~[pgx-api-3.1.0.jar:3.1.0]

      at oracle.pgx.rest.PgxContextListener.contextInitialized(PgxContextListener.java:25) [classes/:?]

      at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4627) [tomcat-embed-core-9.0.8.jar:9.0.8]

      at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5091) [tomcat-embed-core-9.0.8.jar:9.0.8]

      at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) [tomcat-embed-core-9.0.8.jar:9.0.8]

      at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1427) [tomcat-embed-core-9.0.8.jar:9.0.8]

      at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1417) [tomcat-embed-core-9.0.8.jar:9.0.8]

      at java.util.concurrent.FutureTask.run(Unknown Source) [?:1.8.0_201]

      at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75) [tomcat-embed-core-9.0.8.jar:9.0.8]

      at java.util.concurrent.AbstractExecutorService.submit(Unknown Source) [?:1.8.0_201]

      at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:943) [tomcat-embed-core-9.0.8.jar:9.0.8]

      at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:839) [tomcat-embed-core-9.0.8.jar:9.0.8]

      at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) [tomcat-embed-core-9.0.8.jar:9.0.8]

      at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1427) [tomcat-embed-core-9.0.8.jar:9.0.8]

      at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1417) [tomcat-embed-core-9.0.8.jar:9.0.8]

      at java.util.concurrent.FutureTask.run(Unknown Source) [?:1.8.0_201]

      at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75) [tomcat-embed-core-9.0.8.jar:9.0.8]

      at java.util.concurrent.AbstractExecutorService.submit(Unknown Source) [?:1.8.0_201]

      at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:943) [tomcat-embed-core-9.0.8.jar:9.0.8]

      at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:258) [tomcat-embed-core-9.0.8.jar:9.0.8]

      at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) [tomcat-embed-core-9.0.8.jar:9.0.8]

      at org.apache.catalina.core.StandardService.startInternal(StandardService.java:422) [tomcat-embed-core-9.0.8.jar:9.0.8]

      at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) [tomcat-embed-core-9.0.8.jar:9.0.8]

      at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:770) [tomcat-embed-core-9.0.8.jar:9.0.8]

      at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) [tomcat-embed-core-9.0.8.jar:9.0.8]

      at org.apache.catalina.startup.Tomcat.start(Tomcat.java:371) [tomcat-embed-core-9.0.8.jar:9.0.8]

      at oracle.pgx.server.Server.start(Server.java:144) [pgx-server-3.1.0.jar:3.1.0]

      at oracle.pgx.server.Main.main(Main.java:21) [pgx-server-3.1.0.jar:3.1.0]

        • 1. Re: Restarting PGX server using start_server is throwing exception
          Gianni Ceresa
          Gianni Ceresa Feb 21, 2019 10:46 PM (in response to mohanr.k)

          Hi,

          As posted in the other thread, could you please give all the details you can about your environment and version and what you did?

          How to Ask Questions in Developer Community Spaces

          • 2. Re: Restarting PGX server using start_server is throwing exception
            mohanr.k
            mohanr.k Feb 22, 2019 3:16 PM (in response to Gianni Ceresa)

            Configuration file(TestData.json) used to load graph properties is given below. Details about pgx.conf are provided in other thread.

            {

              "jdbc_url": "jdbc:oracle:thin:@<hostname>:1521:pgdb",

              "username": "scott",

              "password": "tiger",

              "format": "pg",

              "db_engine": "rdbms",

              "name": "TestData",

              "vertex_props": [

            { "name": "name", "type": "string" },

            { "name": "type", "type": "string" },

            ],

              "edge_props": [

              { "name": "created_on", "type": "timestamp" },

            ],

              "loading": {

                "load_edge_label": true,

            "load_vertex_labels":true,

            "use_vertex_property_value_as_label":"name"   //This line has been added for 2nd run

              }

            }

             

            As highlighted above graph config file doesn't contain "use_vertex_property_value_as_label":"name" property when I first started PGX server using start_server.bat. Later I realized that I need to add this property to config file so I killed the PGX server by pressing Ctrl+C and then updated the config file with missing property. Now when I start PGX server using start_server.bat its throwing the exception shown above

            • 3. Re: Restarting PGX server using start_server is throwing exception
              Gianni Ceresa
              Gianni Ceresa Feb 22, 2019 4:16 PM (in response to mohanr.k)

              Ok,

              I see what you try to do there. I had a chat a year ago with PMs and architects of PGX and their position was more that there isn't much difference between a label and a property, and having only the properties and not the label for the nodes wasn't an issue as everything still work.

               

              The only little difference is in your PGQL queries where instead of "(n:label)" you need to use something like "(n WITH property_name = value)".

              In my memory in a old (2.3 or there around) version of PGX I couldn't make it work properly that option to identify a property which will become the label when loaded.

              I never tried anymore after as I just started writing all my queries with the "WITH" syntax instead.

               

              I will try again on my 3.1.1 and see if it works better or not now.

              • 4. Re: Restarting PGX server using start_server is throwing exception
                mohanr.k
                mohanr.k Feb 22, 2019 5:57 PM (in response to Gianni Ceresa)

                Thank you.

                 

                I tried with PGX 3.2.0 on windows. I observed this issue there also. Looks like the issue is with adding property use_vertex_property_value_as_label to config file.

                 

                Let me know if it works for you

                • 5. Re: Restarting PGX server using start_server is throwing exception
                  Gianni Ceresa
                  Gianni Ceresa Feb 22, 2019 6:38 PM (in response to mohanr.k)

                  I was testing on PGX 3.1.1 (linux) by loading a graph and I didn't have any error but I also didn't have any label

                  There is a thing which I saw: the table storing vertices in 3.1.1 is different than the previous 2.x.x versions. There is now a VL column which looks like the EL one of the edges tables. I tried entering content there but still didn't have any label loaded.

                   

                  So ... still don't know how to get labels for properties.

                  Will dig a bit more into it over the coming days (also because with that different structure of database tables I need to rewrite some parts of my coming presentations about PGX )

                  • 6. Re: Restarting PGX server using start_server is throwing exception
                    Gianni Ceresa
                    Gianni Ceresa Feb 22, 2019 9:12 PM (in response to mohanr.k)

                    After a bunch of tests I got some vertex labels loaded in my graph.

                     

                    The config generated during the load is the following one:

                    {
"error_handling": {},
"vertex_id_type": "long",
"max_num_connections": 4,
"format": "pg",
"attributes": {},
"password": "*******",
"db_engine": "RDBMS",
"vertex_props": [{
"name": "name",
"type": "string"
}, {
"name": "type",
"type": "string"
}],
"name": "test01",
"loading": {
"load_edge_label": true,
"load_vertex_labels": true,
"use_vertex_property_value_as_label": "type"
},
"edge_props": [],
"jdbc_url": "jdbc:oracle:thin:@localhost:1521/ORCLPDB1",
"username": "scott"
}

                     

                    I also get the same result removing the definition of the "type" vertex property and by removing "load_vertex_labels" as well.

                     

                    On the other hand although there is clearly a column to store labels for vertices in the database I still couldn't find a way to get it loaded so far.

                    • 7. Re: Restarting PGX server using start_server is throwing exception
                      C.H.Lee
                      C.H.Lee Jun 4, 2019 7:32 AM (in response to Gianni Ceresa)

                      Hi, I am using the Bigdatalite VM and if i write

                       

                      graph.queryPgql("SELECT x.name  WHERE (x WITH name = 'John')")

                       

                      it works.

                       

                      # Filter by list

                      may i know how to write 'IS IN' syntax? I have tried

                      "SELECT x.name  WHERE (x WITH name IN ('John','Mary'))"

                      but it couldn't work.

                      • 8. Re: Restarting PGX server using start_server is throwing exception
                        Gianni Ceresa
                        Gianni Ceresa Jun 4, 2019 8:25 AM (in response to C.H.Lee)

                        Hi,

                        IN and NOT IN have been added in PGQL 1.2 (PGQL 1.2 Specification - 20 February 2019 | PGQL · Property Graph Query Language ).

                         

                        If it doesn't work in your case I assume it's because you are on a older version of PGQL?

                        You could check if there is an update for PGX giving you PGQL 1.2 (and other things).

                         

                        I didn't read the spec of PGQL 1.0 and 1.1 for a while, therefore I can't remember if there is a function for that. Last time I needed a quick IN with 2 values I just wrote it like: name = 'John' OR name = 'Mary' .

                        In theory you could also try to get the same result using java_regexp_like and a regexp with the 2 values, but it will be quite hard to maintain and read, for sure more than a good old OR.

                         

                        PS: don't hesitate to create your own thread with questions when you don't find one matching your topic