Querying Gridgain when the cache-value is an array

I have a cache that looks like this:

Key: UUID Value: Array[Long]

I want to get the key corresponding to a specific value. How does the where-part look like?

I have tried "value = ?" and "_value = ?" but these obviously doesnt work.

Solution

Yo!

What do you mean by Array[Long]? Is it just long[] or may be you are using Scala?
The simplest (but not the most effective) way would be using a scan query with predicate (docs here).
To achieve the best performance it is preferable to have your value indexed, so I'd recommend to have a special wrapper class for your array like this:
```
class MyArray implements Comparable<MyArray>, Serializable {
    private long[] arr;

    // implement compareTo,hashCode,equals

    @GridCacheQuerySqlField(index = true)
    public MyArray indexedArray() {
        return this;
    }
}
```
then the query will look like
```
"indexedArray = ?"
```
where as parameter you have to pass MyArray instance. It is a bit dirty way to index value but this is the only way right now.
By the way column names for cache key and value in SQL are _key and _val but not _value and you can write queries like
```
"_val = ? and _key > ?"
```
of course you have to make sure that your key and value at least implement hashCode and equals correctly, implementing Comparable is preferable.