code: @Override
      public Object[] findIdsByColumn(String schemaName, String tableName, String pKeyName, String columnName,
              Object columnValue, Class entityClazz)
      {
          EntityMetadata metadata = KunderaMetadataManager.getEntityMetadata(kunderaMetadata, entityClazz);
  
          List<Object> primaryKeys = new ArrayList<Object>();
  
          DBCollection dbCollection = mongoDb.getCollection(tableName);
          BasicDBObject query = new BasicDBObject();
  
          query.put(columnName, MongoDBUtils.populateValue(columnValue, columnValue.getClass()));
  
          DBCursor cursor = dbCollection.find(query);
          KunderaCoreUtils.printQuery("Find id by column:" + query, showQuery);
          DBObject fetchedDocument = null;
  
          while (cursor.hasNext())
          {
              fetchedDocument = cursor.next();
              Object primaryKey = fetchedDocument.get(pKeyName);
              primaryKey = MongoDBUtils.getTranslatedObject(primaryKey, primaryKey.getClass(), metadata.getIdAttribute()
                      .getJavaType());
              primaryKeys.add(primaryKey);
          }
  
          if (primaryKeys != null && !primaryKeys.isEmpty())
          {
              return primaryKeys.toArray(new Object[0]);
          }
          return null;
  
      }
docs: /*
  (non-Javadoc)
  
  @see com.impetus.kundera.client.Client#findIdsByColumn(java.lang.String,
  java.lang.String, java.lang.String, java.lang.Object, java.lang.Class)