Query Collection (LINKSET, LINKLIST, RIDBAG) Elements from Parent RID

[Bryan]

OrientDB 2.1.2

plocal connection

ODocument API

Hi all,

Evaluating OrientDB, I'm trying to optimize a query that is running out of memory and pretty slow. I'm sure I must be doing something wrong.

Say I have a simple schema like the following:

log 

  + name (String)

  + events (RIDBAG of log_event)

log_event

  + message (String)

  + level (int)

  + timestamp (Date)

and say I want to find all of the log events from a list of logs that have a specified level and order by timestamp...

I.e. "select from (select expand(log_events) from [#10:0, #10:1, #10:4]) where log_level = 1 ORDER BY timestamp ASC LIMIT 1000"

This works fine but when I start to get 100k+ records, things slow down and explode and such. I'm sure my query must be the problem.

So the question is, how can I "efficiently" query collections and get the OIdentifiable or ODocument that satisfy a given condition?

Also, I'm open to using the Java API if that is better...

[Luigi Dell'Aquila]

Hi Bryan,

probably the problems arises because the system has to expand all these big collections in memory.

I'd suggest you to change your model a bit, adding a reverse link from log_event to log (or even better, an edge), so that you can refactor your query like following:

select from log_event where log in [#10:0, #10:1, #10:4] and log.log_level = 1 ORDER BY timestamp ASC LIMIT 1000

this way you will have much more flexibility in adding indexes on log and timestamp properties, it will optimize a lot filtering and sorting and it will also save a lot of memory (sorting is a memory intensive operation)

Luigi

2015-09-17 0:34 GMT+02:00 Bryan <bryan_...@selinc.com>:

OrientDB 2.1.2

plocal connection

ODocument API

Hi all,

Evaluating OrientDB, I'm trying to optimize a query that is running out of memory and pretty slow. I'm sure I must be doing something wrong.

Say I have a simple schema like the following:

log 

  + name (String)

  + events (RIDBAG of log_event)

log_event

  + message (String)

  + level (int)

  + timestamp (Date)

and say I want to find all of the log events from a list of logs that have a specified level and order by timestamp...

I.e. "select from (select expand(log_events) from [#10:0, #10:1, #10:4]) where log_level = 1 ORDER BY timestamp ASC LIMIT 1000"

This works fine but when I start to get 100k+ records, things slow down and explode and such. I'm sure my query must be the problem.

So the question is, how can I query collections and get the OIdentifiable or ODocument that satisfy a given condition?

--

---
You received this message because you are subscribed to the Google Groups "OrientDB" group.
To unsubscribe from this group and stop receiving emails from it, send an email to orient-databa...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.