Selecting based on key (a unique identifier) in google appengine [Java]

Posted by Stavros on Stack Overflow See other posts from Stack Overflow or by Stavros
Published on 2010-05-23T23:37:01Z Indexed on 2010/05/23 23:40 UTC
Read the original article Hit count: 249

Filed under:

java

|

google-app-engine

|

gql

I have

public class QuantityType {
    @PrimaryKey
    @Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
    private Key key;

    @Persistent
    private String type;
}

I am trying to setup a query to get the right QuantityType by it's key

gql = "select * from QuantityType where __key__='aght52oobW1hIHTWVzc2FnZRiyAQw'";

But its not working because

BadFilterError: BadFilterError: invalid filter: key filter value must be a Key; received aght52oobW1hIHTWVzc2FnZRiyAQw (a str).

I have also tried to use

gql = "select * from QuantityType where __key__=='" + KeyFactory.stringToKey(qTypeKey)+"'";

but it's now working..

How can I get a specific object from my datastore by it's key?

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