delta index in Ultrasphinx

Hello, all

I have a problem with delta index in Ultrasphinx.

My configuration:

using config file
'/home/tolya/test_sphinx/config/ultrasphinx/development.conf'...
indexing index 'delta'...
collected 0 docs, 0.0 MB
total 0 docs, 0 bytes
total 0.023 sec, 0.00 bytes/sec, 0.00 docs/sec
rotating indices: succesfully sent SIGHUP to searchd (pid=3224).
Index rotated ok

You can tell thinks have gone wrong at this stage: the index should have picked up at least 1 document

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but in console:
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./script/console
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Loading development environment (Rails 2.1.0)

@s = Ultrasphinx::Search.new(:query => 'zzzxxxccc').run
@s.results

=> []
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Where is i make mistake? Why Ultrasphinx doesn't find "zzzxxxccc"?

In the attachment is locate my development.conf.

Sphinx is using the updated_at column to decide which rows should be in the delta index. However you haven't set updated_at

Fred

thank you very much!