gin_fuzzy_search_limit description

Hi,

I'm not very clear on what this is supposed to mean. The description in
guc.c is this:

Sets the maximum allowed result for exact search by GIN.

Say again?

The involved code is this:

if (GinFuzzySearchLimit > 0)
{
/*
* If all of keys more than treshold we will try to reduce result,
* we hope (and only hope, for intersection operation of array our
* supposition isn't true), that total result will not more than
* minimal predictNumberResult.
*/

for (i = 0; i < key->nentries; i++)
if (key->scanEntry[i].predictNumberResult <= key->nentries * GinFuzzySearchLimit)
return;

for (i = 0; i < key->nentries; i++)
if (key->scanEntry[i].predictNumberResult > key->nentries * GinFuzzySearchLimit)
{
key->scanEntry[i].predictNumberResult /= key->nentries;
key->scanEntry[i].reduceResult = TRUE;
}
}
(ginget.c, startScanKey)

The source comment is not very clear either :-) And I'm not sure I
follow what the code is doing.

Can anyone clarify?

--
Alvaro Herrera http://www.CommandPrompt.com/
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