IMap vs MultiMap

[Neil Martin]

If I have an IMap that's typed as follows - IMap<K, Set<V>>, can I still use a predicate that references the keys?  Assuming the key is "id", would I be able to do something like this as a predicate :  "id IN (1,2,3,4,5)"?  Thus enabling me to look up the values for multiple keys in a single operation.

I know I can use a MultiMap to store multiple values at a key, but one get can only lookup the values for a single key at a time.

[Enes Akar]

You can use predicate builder as follows:

        HazelcastInstance instance = Hazelcast.newHazelcastInstance(null);
        IMap<String, String> map = instance.getMap("map");
        map.put("key1", "value1");
        map.put("key2", "value2");
        EntryObject e = new PredicateBuilder().getEntryObject();
        Predicate p1 = e.key().equal("key1");
        Predicate predicate = e.key().equal("key2").or(p1);
        Collection values = map.values(predicate);
        System.out.println(values.size());

On Sat, Jul 7, 2012 at 6:02 AM, Neil Martin <nsm...@gmail.com> wrote:

If I have an IMap that's typed as follows - IMap<K, Set<V>>, can I still use a predicate that references the keys?  Assuming the key is "id", would I be able to do something like this as a predicate :  "id IN (1,2,3,4,5)"?  Thus enabling me to look up the values for multiple keys in a single operation.

I know I can use a MultiMap to store multiple values at a key, but one get can only lookup the values for a single key at a time.

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[Neil Martin]

Thanks for the reply, although I think I need some clarification.  Should I assume that since you posted an example of a custom predicate, that I can't solve this with a SqlPredicate?  Just want to make sure I'm not missing something...

On Monday, July 9, 2012 2:33:13 AM UTC-5, Enes Akar wrote:

You can use predicate builder as follows:

        HazelcastInstance instance = Hazelcast.newHazelcastInstance(null);
        IMap<String, String> map = instance.getMap("map");
        map.put("key1", "value1");
        map.put("key2", "value2");
        EntryObject e = new PredicateBuilder().getEntryObject();
        Predicate p1 = e.key().equal("key1");
        Predicate predicate = e.key().equal("key2").or(p1);
        Collection values = map.values(predicate);
        System.out.println(values.size());

On Sat, Jul 7, 2012 at 6:02 AM, Neil Martin wrote:

If I have an IMap that's typed as follows - IMap<K, Set<V>>, can I still use a predicate that references the keys?  Assuming the key is "id", would I be able to do something like this as a predicate :  "id IN (1,2,3,4,5)"?  Thus enabling me to look up the values for multiple keys in a single operation.

I know I can use a MultiMap to store multiple values at a key, but one get can only lookup the values for a single key at a time.

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[Enes Akar]

Yes currently it is not possible with sql-predicate.

But for such a feature you may create an enhancement issue on github.

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