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Clean up the random number example #7

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Clean up the random number example #7

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9 changes: 3 additions & 6 deletions content/patterns/random-attribute.txt
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Original file line number Diff line number Diff line change
Expand Up @@ -79,19 +79,16 @@ your number against the stored attribute.

<% code 'javascript' do %>
> rand = Math.random()
> cmp = Math.random()
> result = db.docs.findOne( { key : 2, random : { $gte : rand } } )
> if ( result == null ) {
> result = db.docs.findOne( { key : 2, random : { $lte : rand } } )
> result = db.docs.findOne( { key : 2, random : { $lt : rand } } )
> }
<% end %>


Note that we're not going for equality alone because the chances of
that to occur are low. So we try either '$gte' or '$lte' with equal
probability but knowing that in some cases it may not return a result,
even though there are documents in the result. For that reason, an
empty result must be verified by doing a search in the opposite
that to occur are low. So we try '$gte', and as there is a possibility
of it may not return a result, we must do a search in the opposite
direction.

The final -- but important -- detail about this query is that both the
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