OrientDB 1.6.3: ClassCastException expanding a field (OTrackedMap, OIdentifiable)

[andrii0lomakin]

Hi!
I am facing with a very weird behaviour of a select statement.
I cannot execute expand() or contains() function because a ClassCastException is raised or no records at all are returned.

I have a "games" class that for out test, at the moment contains just one record:
"@Rid": "#24:0",
"@Version": 2,
"@Class": "games",
"players": [
{
"username": "[email protected]",
"name": "john doe",
"points": 0
},
{
"username": "[email protected]",
"name": "jane doe",
"department": "one",
"points": 0
},
{
"username": "[email protected]",
"name": "dana scully",
"department": "two",
"points": 0
}
],
"status": "open",
"player_turn": 0,
"id": "ff342a9b-79cd-4494-983e-6ec4a1a47c8a",
"_creation_date": "2014-02-15T13:49:51.051+0100",
"_author": "admin"

As you can see the field "players" is a collection of JSON objects.
If I perform a query against the class I have:
orientdb> select from games
----+-----+-------+------+-----------+------------------------------------+-------+------+------+----------------------------+-------

|@Rid |players|status|player_turn|id |_links |_audit|_allow|_creation_date |_author

----+-----+-------+------+-----------+------------------------------------+-------+------+------+----------------------------+-------
0 |#24:0|[3] |open |0 |ff342a9b-79cd-4494-983e-6ec4a1a47c8a|#11:383|#3:370|[1] |2014-02-15T13:49:51.051+0100|admin
----+-----+-------+------+-----------+------------------------------------+-------+------+------+----------------------------+-------

or:
orientdb> select @this.toJson() from games
----+-----+-----------------------------------------------------------------------------------------------------------------

|@Rid |this

----+-----+-----------------------------------------------------------------------------------------------------------------
0 |#-2:1|{"@type":"d","@Rid":"#24:0","@Version":2,"@Class":"games","players":[{"username":"[email protected]","name":"john ...
----+-----+-----------------------------------------------------------------------------------------------------------------
1 item(s) found. Query executed in 0.041 sec(s).

Everything seems to be fine.
However when I try to expand the players field I have this error:

orientdb> select expand(players) from games
Error: com.orientechnologies.orient.core.exception.OCommandExecutionException: Error on execution of command: sql.select expand(players) from games
Error: java.lang.ClassCastException: com.orientechnologies.orient.core.db.record.OTrackedMap cannot be cast to com.orientechnologies.orient.core.db.re
cord.OIdentifiable

Furthermore I cannot execute any selection criteria against the players field:
orientdb> select from games where players contains (username = "[email protected]")
0 item(s) found. Query executed in 0.0020 sec(s).

orientdb> select from games where players[username] = "[email protected]"
0 item(s) found. Query executed in 0.0040 sec(s).

orientdb> select from games where players[username = "[email protected]"]
Error: com.orientechnologies.orient.core.exception.OCommandExecutionException: Error on execution of command: sql.select from games where players[user
name = "[email protected]"]
Caused by: com.orientechnologies.orient.core.exception.OCommandExecutionException: Error on execution of command: sql.select expand(players) from games
at com.orientechnologies.orient.core.storage.OStorageEmbedded.executeCommand(OStorageEmbedded.java:102)
at com.orientechnologies.orient.core.storage.OStorageEmbedded.command(OStorageEmbedded.java:85)
at com.orientechnologies.orient.core.sql.query.OSQLQuery.run(OSQLQuery.java:69)
at com.orientechnologies.orient.core.sql.query.OSQLSynchQuery.run(OSQLSynchQuery.java:82)
at com.orientechnologies.orient.core.query.OQueryAbstract.execute(OQueryAbstract.java:29)
... 26 more
Caused by: java.lang.ClassCastException: com.orientechnologies.orient.core.db.record.OTrackedMap cannot be cast to com.orientechnologies.orient.core.d
b.record.OIdentifiable
at com.orientechnologies.orient.core.sql.OCommandExecutorSQLResultsetAbstract.getResult(OCommandExecutorSQLResultsetAbstract.java:163)
at com.orientechnologies.orient.core.sql.OCommandExecutorSQLSelect.execute(OCommandExecutorSQLSelect.java:340)
at com.orientechnologies.orient.core.sql.OCommandExecutorSQLDelegate.execute(OCommandExecutorSQLDelegate.java:57)
at com.orientechnologies.orient.core.storage.OStorageEmbedded.executeCommand(OStorageEmbedded.java:96)
... 30 more

and this is the second one:
Caused by: com.orientechnologies.orient.core.exception.OCommandExecutionException: Error on execution of command: sql.select from games where ( players[username="[email protected]"] )
at com.orientechnologies.orient.core.storage.OStorageEmbedded.executeCommand(OStorageEmbedded.java:102)
at com.orientechnologies.orient.core.storage.OStorageEmbedded.command(OStorageEmbedded.java:85)
at com.orientechnologies.orient.core.sql.query.OSQLQuery.run(OSQLQuery.java:69)
at com.orientechnologies.orient.core.sql.query.OSQLSynchQuery.run(OSQLSynchQuery.java:82)
at com.orientechnologies.orient.core.query.OQueryAbstract.execute(OQueryAbstract.java:29)
... 26 more
Caused by: java.lang.ClassCastException: com.orientechnologies.orient.core.db.record.OTrackedMap cannot be cast to java.lang.Boolean
at com.orientechnologies.orient.core.sql.OCommandExecutorSQLResultsetAbstract.evaluateRecord(OCommandExecutorSQLResultsetAbstract.java:317)
at com.orientechnologies.orient.core.sql.OCommandExecutorSQLResultsetAbstract.filter(OCommandExecutorSQLResultsetAbstract.java:310)
at com.orientechnologies.orient.core.sql.OCommandExecutorSQLSelect.executeSearchRecord(OCommandExecutorSQLSelect.java:401)
at com.orientechnologies.orient.core.sql.OCommandExecutorSQLSelect.executeSearch(OCommandExecutorSQLSelect.java:364)
at com.orientechnologies.orient.core.sql.OCommandExecutorSQLSelect.execute(OCommandExecutorSQLSelect.java:333)
at com.orientechnologies.orient.core.sql.OCommandExecutorSQLDelegate.execute(OCommandExecutorSQLDelegate.java:57)
at com.orientechnologies.orient.core.storage.OStorageEmbedded.executeCommand(OStorageEmbedded.java:96)
... 30 more

[lvca]

players seems to be a map. If you want to use as target of another select (like the one with expand()) you should call it against players.values() to return the collection of values.

[giastfader]

Hi Luca,
I tried with players.values() but nothing is returned:

orientdb> select players.values() from games
----+-----
#   |@RID
----+-----
0   |#-2:1
----+-----
1 item(s) found. Query executed in 0.152 sec(s).

[lvca]

By looking at your JSON that isn't a MAP but a collection. So I don't know why a OTrackedMap object goes there. Could you debug in what case that OTrackedMap object goes in tempResult variable of the SQL select command?

[giastfader]

Ok, I will try it

[giastfader]

Hi,
executing this query:

select from games where players[username="[email protected]"]

the problem is generated by the method OCommandExecutorSQLResultsetAbstract.evaluateRecord(), at this line:

    return (Boolean) compiledFilter.evaluate(iRecord, null, context);

The problem is that in this case the evaluate() method does not return a Boolean but an instance of OTrackedMap.
This because the parser executes the OSQLFilterCondition.evaluate() method and here happens the problem:

   if (operator == null) {
      if (l == null)
        // THE LEFT RETURNED NULL
        return Boolean.FALSE;

      // UNITARY OPERATOR: JUST RETURN LEFT RESULT
      return l;
    }

Actually operator is null and since l is not null l itself is returned.
l variable is an instance of the OTrackedMap class.
This variable then goes up through the stack:

OSQLFilterCondition.evaluate(OIdentifiable, ODocument, Object, OCommandContext) line: 296
OSQLFilterCondition.evaluate(OIdentifiable, ODocument, OCommandContext) line: 73
OSQLFilter.evaluate(ORecord, ODocument, OCommandContext) line: 63 OCommandExecutorSQLSelect(OCommandExecutorSQLResultsetAbstract).evaluateRecord(ORecord) line: 317

and generates the ClassCastExeption error.

Actually it seems that the variable tempResult is never involved.

[lvca]

Probably after the return that Map goes in the tempResult. So why are you writing a query like that?

[giastfader]

I just want to extract all records that contain at least one player with the given email address.
As I wrote I tried different ways and no one seems to work.
Debugging the code I found that actually the filter works and right records are extracted, but that error occurs and the reply is never returned.
I'm open to any advice on how extract the right records.
However I think that the server should never throws a ClassCastException.

[lvca]

Why don't you use:

select from games where players contains ( username = "[email protected]" )

[giastfader]

it returns no records

[giastfader]

Ok, I digged into the code.
It seems that because players is an embedded collection, when the condition username = "[email protected]" is evaluated it returns false because the check is executed against the record, not against the items belonging to the players collection.

I think that the problem is in OSQLFilterItemField.getValue().
It is invoked with the following parameters:

iRecord=games#29:2{players:[3],status:open,player_turn:0,id:e0e39261-a473-4d7e-b528-388bbaa7d215,_links:#11:19,_audit:#3:49,_allow:[1],_allowRead:null,_allowWrite:null,_allowUpdate:null,_allowDelete:null,_creation_date:Fri Feb 21 15:57:12 CET 2014,_author:admin} v2
iContext: {current=games#29:2{players:[3],status:open,player_turn:0,id:e0e39261-a473-4d7e-b528-388bbaa7d215,_links:#11:19,_audit:#3:49,_allow:[1],_allowRead:null,_allowWrite:null,_allowUpdate:null,_allowDelete:null,_creation_date:Fri Feb 21 15:57:12 CET 2014,_author:admin} v2}
name (field of the OSQLFilterItemField instance): username

At line 62:

 Object v = ODocumentHelper.getFieldValue(doc, name);

the method getFieldValue() returns null and then all the statement is evaluated as false.

In other words the filed "username" isn't found inside the record

[lvca]

Can you provide a fix for it? Or a database to debug on that point?

[giastfader]

Those methods are the focal points of the SQL parser, I woudn't make some damage making something wrong.
I send you the DB via email.
Thanks