how to load values from google app engine data store for OR operation using java

Question

I have to load entity values by using 2 conditions using OR condition For example, SELECT * FROM db WHERE (email = xyz@gmail.com OR UUID = 1234) .

Have tried using Filter:

Filter emailFilter =
              new FilterPredicate("email", FilterOperator.EQUAL, email);

Filter firstFilter =
              new FilterPredicate("firstname", FilterOperator.EQUAL, firstName);

Filter filter =
              CompositeFilterOperator.or(emailFilter, firstFilter);

But I don't understand how to use this filter while loading...

How can I do this using filter in datastore?

Answer 1

If I understand you correctly, you just need to apply the filter to a query and retrieve the results:

// Your filter declarations
Filter emailFilter =
    new FilterPredicate("email", FilterOperator.EQUAL, email);
Filter firstFilter =
    new FilterPredicate("firstname", FilterOperator.EQUAL, firstName);
Filter filter =
    CompositeFilterOperator.or(emailFilter, firstFilter);

// Use class Query to assemble a query
Query q = new Query("Person").setFilter(filter)

// Use PreparedQuery interface to retrieve results
PreparedQuery pq = datastore.prepare(q);

for (Entity result : pq.asIterable()) {
    // result.getProperty("lastname")
}