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Comment by peterknego | Hacker News Reader

A GAE datastore delete takes multiple operations because it also updates indexes:

1 entity delete = 2 Writes + 2 Writes per indexed property value + 1 Write per composite index value

Well, the OP is just another coder who can't read docs, but can write a blog.

Regardless of how decent Google's AppEngine documentation is, this is indeed a bug.

The correct behavior would be to recalculate the indices just once, instead of reindexing after every single delete operation.

It then becomes

    2*entities + 2*indexed property values + composite index values

operations to delete all entities in the datastore, instead of

    2*entities + 2*entities*indexed property values + entities*composite index values

operations.

To delete all entities should be free. Who cares about indexes? `rm -rf`, done.

In any case, good that something is pointed out that can and will be easily overlooked :)

I deleted all indices referencing those entities before starting the entity deletions.