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我試圖從數據庫中獲取條目,需要按流派對其進行過濾:Google App Engine Java數據存儲查詢 - 限制結果?
<%@ page import="com.google.appengine.api.datastore.Query.Filter"%>
<%@ page import="com.google.appengine.api.datastore.Query.FilterPredicate"%>
<%@ page import="com.google.appengine.api.datastore.Query.FilterOperator"%>
<%@ page import="com.google.appengine.api.datastore.*"%>
<%@ page import="com.google.appengine.api.datastore.Query.*"%>
Query confQuery = new Query("Track");
Query.Filter topicFilter = new FilterPredicate("genre",
FilterOperator.EQUAL, genre);
confQuery.setFilter(topicFilter);
confQuery.addSort("lastplayed", SortDirection.ASCENDING);
PreparedQuery results = datastore.prepare(confQuery);
這將始終與給定類型返回的所有條目。我怎樣才能限制這個10項?
FetchOptions.Builder.withLimit(10) – 4ndro1d