JDOQL isn't SQL, so I'm not surprised that this isn't working. It's not
possible to retrieve only parts of an entity, so this syntax wouldn't have
made a whole lot of sense. An alternate method of doing a Key only query is
to use the low-level API:
http://code.google.com/appengine/docs/java/javadoc/com/google/appengine/api/datastore/Query.html#setKeysOnly()
http://code.google.com/appengine/docs/java/javadoc/com/google/appengine/api/datastore/Query.html#setKeysOnly()When
you form a query, set it to Keys only rather than retrieving complete
entities. What this mean is that this only hits your indexes, returning the
subset of keys that match. You can then use these Keys as you would normally
use them.
On Fri, Dec 25, 2009 at 5:38 PM, giridhar kannan g.giridharkan...@gmail.com
wrote:
hi all,
i would like to know how to use the query
b select __key__ from Class-Name /b in java .
The same syntax is not working, it shows the following
b PrimaryExpression should be a VariableExpression with name
__key__ /b
Please do help me.
Thank you.
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