在Google数据存储中根据自动生成的ID选择实体 [英] Selecting Entity based on auto generated ID in google datastore
问题描述
我创建了一个具有很少属性的实体,但没有指定任何键,在这种情况下,自动生成的ID已经在数据存储中创建。 code> Entity en = new Entity(Job);
现在,当我获取这些实体并尝试将其存储在Java对象中时,如何获取auto生成的ID(我需要稍后执行UPDATE操作)?
我尝试了以下方法,但它不返回标识符值。
en.getProperty(__ key__) ;
en.getProperty(ID / Name);
en.getProperty(Key);
您可能正在寻找:
en.getProperty(Entity.KEY_RESERVED_PROPERTY)
$在键过滤器中提到的b $ b
(不是
另一种方法是尝试:
en.getKey().getId()
I have created an entity with few attributes but without specifying any key in which case an auto generated ID has been created in data-store.
Entity en=new Entity("Job");
Now when I fetch such entities and try to store it in Java object, how can I get the auto generated ID (which I required to perform UPDATE operation later)? I have tried the below ways but it does not return Identifier value.
en.getProperty("__key__");
en.getProperty("ID/Name");
en.getProperty("Key");
You are probably looking for:
en.getProperty(Entity.KEY_RESERVED_PROPERTY)
mentioned in Key Filters (not an obvious place to find it).
Another approach would be to try:
en.getKey().getId()
mentioned in Entity JavaDoc and Key JavaDoc.
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