function MakeSuggestion($keyword, $ln)
{
$trigrams = BuildTrigrams($keyword);
$query = "\"{$trigrams}\"/1";
$len = strlen($keyword);
$delta = LENGTH_THRESHOLD;
$weight = 'weight()';
if (SPHINX_20 == true) {
$weight = '@weight';
}
$stmt = $ln->prepare("SELECT *, {$weight} as w, w+:delta-ABS(len-:len) as myrank FROM suggest WHERE MATCH(:match) AND len BETWEEN :lowlen AND :highlen\r\n\t\t\tORDER BY myrank DESC, freq DESC\r\n\t\t\tLIMIT 0,:topcount OPTION ranker=wordcount");
$stmt->bindValue(':match', $query, PDO::PARAM_STR);
$stmt->bindValue(':len', $len, PDO::PARAM_INT);
$stmt->bindValue(':delta', $delta, PDO::PARAM_INT);
$stmt->bindValue(':lowlen', $len - $delta, PDO::PARAM_INT);
$stmt->bindValue(':highlen', $len + $delta, PDO::PARAM_INT);
$stmt->bindValue(':topcount', TOP_COUNT, PDO::PARAM_INT);
$stmt->execute();
if (!($rows = $stmt->fetchAll())) {
return false;
}
// further restrict trigram matches with a sane Levenshtein distance limit
foreach ($rows as $match) {
$suggested = $match["keyword"];
if (levenshtein($keyword, $suggested) <= LEVENSHTEIN_THRESHOLD) {
return $suggested;
}
}
return $keyword;
}
function MakeSuggestion($keyword)
{
$trigrams = BuildTrigrams($keyword);
$query = "\"{$trigrams}\"/1";
$len = strlen($keyword);
$delta = LENGTH_THRESHOLD;
$cl = new SphinxClient();
$cl->SetMatchMode(SPH_MATCH_EXTENDED2);
$cl->SetRankingMode(SPH_RANK_WORDCOUNT);
$cl->SetFilterRange("len", $len - $delta, $len + $delta);
$cl->SetSelect("*, @weight+{$delta}-abs(len-{$len}) AS myrank");
$cl->SetSortMode(SPH_SORT_EXTENDED, "myrank DESC, freq DESC");
$cl->SetArrayResult(true);
// pull top-N best trigram matches and run them through Levenshtein
$cl->SetLimits(0, TOP_COUNT);
$res = $cl->Query($query, "suggest");
if (!$res || !$res["matches"]) {
return false;
}
if (SUGGEST_DEBUG) {
print "--- DEBUG START ---\n";
foreach ($res["matches"] as $match) {
$w = $match["attrs"]["keyword"];
$myrank = @$match["attrs"]["myrank"];
if ($myrank) {
$myrank = ", myrank={$myrank}";
}
// FIXME? add costs?
// FIXME! does not work with UTF-8.. THIS! IS!! PHP!!!
$levdist = levenshtein($keyword, $w);
print "id={$match['id']}, weight={$match['weight']}, freq={$match[attrs][freq]}{$myrank}, word={$w}, levdist={$levdist}\n";
}
print "--- DEBUG END ---\n";
}
// further restrict trigram matches with a sane Levenshtein distance limit
foreach ($res["matches"] as $match) {
$suggested = $match["attrs"]["keyword"];
if (levenshtein($keyword, $suggested) <= LEVENSHTEIN_THRESHOLD) {
return $suggested;
}
}
return $keyword;
}
