问题
If I found information about removing unused indexes, like in Uploading and Managing a Python App / Deleting Unused Indexes, it was only for the Python environment...
Any way to tag an index in the [~project]/war/WEB-INF/datastore-indexes.xml file?
回答1:
Since version 1.4.2 the Java SDK supports the vacuum_indexes action. Run this command to delete unused indices:
./<appengine-java-sdk-path>/bin/appcfg.sh vacuum_indexes <myapp-path>/war
On Windows with the Eclipse SDK it's something like:
<eclipse-path>\plugins\com.google.appengine.eclipse.sdkbundle_1.4.3.v201103311225\appengine-java-sdk-1.4.3\bin\appcfg.cmd vacuum_indexes <myapp-path>\war
回答2:
The only way you currently can remove an index is using the Python SDK as described here.
The missing vacuum_indexes functionality from the Java SDK is logged as a bug, but not yet fixed.
来源：https://stackoverflow.com/questions/2128739/google-app-engine-java-how-to-remove-unused-indexes