在Couchbase Lite视图中查询多个键 [英] Query multiple keys in couchbase lite view

问题描述

我是不熟悉长沙发/沙发底座-精简版的人，我尝试使用多个键查询视图，但未成功.她是map函数的外观:

Hi I am new to couchbase/couchbase-lite and i try to query a view with multiple keys without success. Her is how the map function looks:

public void map(Map<String, Object> doc, Emitter emitter) {
    if (doc.get("type").equals("my_type") {
        List<Object> keys = new ArrayList<Object>();
        keys.add(doc.get("key_1"));
        keys.add(doc.get("key_2"));
        emitter.emit(keys, null); 
    }   
}

我的问题是我只需要使用key_1或使用key_1和key_2的组合来查询视图

My problem is that i need to query the view either only with key_1 or with a combination of key_1 and key_2 like so

List<Object> keys = new ArrayList<Object>();
keys.add(key_1);
if (key_2 != null) keys.add(key_2);
query.setKeys(keys);
results = query.run()

但是结果始终为空.我会忽略任何东西吗?

However the results are always empty. Do i overlook anything?

推荐答案

两次发射不起作用.如果在setKeys()方法中提供ArrayList，则List中的每个键都与emit中的每个键匹配.如果要匹配两个键，请将键ArrayList添加到另一个列表中.然后将其传递给setKeys()方法.像这样

Two emits doesn't work. If you give a ArrayList in setKeys() method, each key in the List match the each key in emit. If you want to match two keys, add keys ArrayList into another List. Then pass it to setKeys() method. Like this,

List<Object> keys = new ArrayList<Object>();
List<Object> allKeys = new ArrayList<Object>();
keys.add(key_1);
if (key_2 != null) keys.add(key_2);
allKeys.add(keys);
query.setKeys(allKeys);
results = query.run();

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