]> git.openstreetmap.org Git - nominatim.git/blobdiff - lib/SearchDescription.php
Merge pull request #1647 from lonvia/split-out-linking
[nominatim.git] / lib / SearchDescription.php
index e949585208feef8062e5aa1924518dfbee1b49cf..4fafbec2b21c9899fb1e35c51ac8241647876b58 100644 (file)
@@ -17,6 +17,8 @@ class SearchDescription
     private $sCountryCode = '';
     /// List of word ids making up the name of the object.
     private $aName = array();
+    /// True if the name is rare enough to force index use on name.
+    private $bRareName = false;
     /// List of word ids making up the address of the object.
     private $aAddress = array();
     /// Subset of word ids of full words making up the address.
@@ -43,7 +45,6 @@ class SearchDescription
     /// Index of phrase currently processed.
     private $iNamePhrase = -1;
 
-
     /**
      * Create an empty search description.
      *
@@ -58,7 +59,7 @@ class SearchDescription
     /**
      * Get current search rank.
      *
-     * The higher the search rank the lower the likelyhood that the
+     * The higher the search rank the lower the likelihood that the
      * search is a correct interpretation of the search query.
      *
      * @return integer Search rank.
@@ -94,8 +95,8 @@ class SearchDescription
      */
     public function looksLikeFullAddress()
     {
-        return sizeof($this->aName)
-               && (sizeof($this->aAddress || $this->sCountryCode))
+        return (!empty($this->aName))
+               && (!empty($this->aAddress) || $this->sCountryCode)
                && preg_match('/[0-9]+/', $this->sHouseNumber);
     }
 
@@ -147,7 +148,7 @@ class SearchDescription
      */
     public function isValidSearch()
     {
-        if (!sizeof($this->aName)) {
+        if (empty($this->aName)) {
             if ($this->sHouseNumber) {
                 return false;
             }
@@ -165,30 +166,29 @@ class SearchDescription
     /**
      * Derive new searches by adding a full term to the existing search.
      *
-     * @param mixed[] $aSearchTerm  Description of the token.
-     * @param bool    $bHasPartial  True if there are also tokens of partial terms
-     *                              with the same name.
-     * @param string  $sPhraseType  Type of phrase the token is contained in.
-     * @param bool    $bFirstToken  True if the token is at the beginning of the
-     *                              query.
-     * @param bool    $bFirstPhrase True if the token is in the first phrase of
-     *                              the query.
-     * @param bool    $bLastToken   True if the token is at the end of the query.
+     * @param object $oSearchTerm  Description of the token.
+     * @param bool   $bHasPartial  True if there are also tokens of partial terms
+     *                             with the same name.
+     * @param string $sPhraseType  Type of phrase the token is contained in.
+     * @param bool   $bFirstToken  True if the token is at the beginning of the
+     *                             query.
+     * @param bool   $bFirstPhrase True if the token is in the first phrase of
+     *                             the query.
+     * @param bool   $bLastToken   True if the token is at the end of the query.
      *
      * @return SearchDescription[] List of derived search descriptions.
      */
-    public function extendWithFullTerm($aSearchTerm, $bHasPartial, $sPhraseType, $bFirstToken, $bFirstPhrase, $bLastToken)
+    public function extendWithFullTerm($oSearchTerm, $bHasPartial, $sPhraseType, $bFirstToken, $bFirstPhrase, $bLastToken)
     {
         $aNewSearches = array();
 
         if (($sPhraseType == '' || $sPhraseType == 'country')
-            && !empty($aSearchTerm['country_code'])
-            && $aSearchTerm['country_code'] != '0'
+            && is_a($oSearchTerm, '\Nominatim\Token\Country')
         ) {
             if (!$this->sCountryCode) {
                 $oSearch = clone $this;
                 $oSearch->iSearchRank++;
-                $oSearch->sCountryCode = $aSearchTerm['country_code'];
+                $oSearch->sCountryCode = $oSearchTerm->sCountryCode;
                 // Country is almost always at the end of the string
                 // - increase score for finding it anywhere else (optimisation)
                 if (!$bLastToken) {
@@ -197,15 +197,12 @@ class SearchDescription
                 $aNewSearches[] = $oSearch;
             }
         } elseif (($sPhraseType == '' || $sPhraseType == 'postalcode')
-                  && $aSearchTerm['class'] == 'place' && $aSearchTerm['type'] == 'postcode'
+                  && is_a($oSearchTerm, '\Nominatim\Token\Postcode')
         ) {
             // We need to try the case where the postal code is the primary element
             // (i.e. no way to tell if it is (postalcode, city) OR (city, postalcode)
             // so try both.
-            if (!$this->sPostcode
-                && $aSearchTerm['word']
-                && pg_escape_string($aSearchTerm['word']) == $aSearchTerm['word']
-            ) {
+            if (!$this->sPostcode) {
                 // If we have structured search or this is the first term,
                 // make the postcode the primary search element.
                 if ($this->iOperator == Operator::NONE
@@ -216,70 +213,82 @@ class SearchDescription
                     $oSearch->iOperator = Operator::POSTCODE;
                     $oSearch->aAddress = array_merge($this->aAddress, $this->aName);
                     $oSearch->aName =
-                        array($aSearchTerm['word_id'] => $aSearchTerm['word']);
+                        array($oSearchTerm->iId => $oSearchTerm->sPostcode);
                     $aNewSearches[] = $oSearch;
                 }
 
                 // If we have a structured search or this is not the first term,
                 // add the postcode as an addendum.
                 if ($this->iOperator != Operator::POSTCODE
-                    && ($sPhraseType == 'postalcode' || sizeof($this->aName))
+                    && ($sPhraseType == 'postalcode' || !empty($this->aName))
                 ) {
                     $oSearch = clone $this;
                     $oSearch->iSearchRank++;
-                    $oSearch->sPostcode = $aSearchTerm['word'];
+                    $oSearch->sPostcode = $oSearchTerm->sPostcode;
                     $aNewSearches[] = $oSearch;
                 }
             }
         } elseif (($sPhraseType == '' || $sPhraseType == 'street')
-                 && $aSearchTerm['class'] == 'place' && $aSearchTerm['type'] == 'house'
+                 && is_a($oSearchTerm, '\Nominatim\Token\HouseNumber')
         ) {
             if (!$this->sHouseNumber && $this->iOperator != Operator::POSTCODE) {
                 $oSearch = clone $this;
                 $oSearch->iSearchRank++;
-                $oSearch->sHouseNumber = trim($aSearchTerm['word_token']);
+                $oSearch->sHouseNumber = $oSearchTerm->sToken;
                 // sanity check: if the housenumber is not mainly made
                 // up of numbers, add a penalty
-                if (preg_match_all("/[^0-9]/", $oSearch->sHouseNumber, $aMatches) > 2) {
+                if (preg_match('/\\d/', $oSearch->sHouseNumber) === 0
+                    || preg_match_all('/[^0-9]/', $oSearch->sHouseNumber, $aMatches) > 2) {
                     $oSearch->iSearchRank++;
                 }
-                if (!isset($aSearchTerm['word_id'])) {
+                if (empty($oSearchTerm->iId)) {
                     $oSearch->iSearchRank++;
                 }
                 // also must not appear in the middle of the address
-                if (sizeof($this->aAddress) || sizeof($this->aAddressNonSearch)) {
+                if (!empty($this->aAddress)
+                    || (!empty($this->aAddressNonSearch))
+                    || $this->sPostcode
+                ) {
                     $oSearch->iSearchRank++;
                 }
                 $aNewSearches[] = $oSearch;
             }
-        } elseif ($sPhraseType == '' && $aSearchTerm['class']) {
+        } elseif ($sPhraseType == ''
+                  && is_a($oSearchTerm, '\Nominatim\Token\SpecialTerm')
+        ) {
             if ($this->iOperator == Operator::NONE) {
                 $oSearch = clone $this;
                 $oSearch->iSearchRank++;
 
-                $iOp = Operator::NEAR; // near == in for the moment
-                if ($aSearchTerm['operator'] == '') {
-                    if (sizeof($this->aName)) {
+                $iOp = $oSearchTerm->iOperator;
+                if ($iOp == Operator::NONE) {
+                    if (!empty($this->aName) || $this->oContext->isBoundedSearch()) {
                         $iOp = Operator::NAME;
+                    } else {
+                        $iOp = Operator::NEAR;
                     }
                     $oSearch->iSearchRank += 2;
                 }
 
-                $oSearch->setPoiSearch($iOp, $aSearchTerm['class'], $aSearchTerm['type']);
+                $oSearch->setPoiSearch(
+                    $iOp,
+                    $oSearchTerm->sClass,
+                    $oSearchTerm->sType
+                );
                 $aNewSearches[] = $oSearch;
             }
-        } elseif (isset($aSearchTerm['word_id'])
-                  && $aSearchTerm['word_id']
-                  && $sPhraseType != 'country'
+        } elseif ($sPhraseType != 'country'
+                  && is_a($oSearchTerm, '\Nominatim\Token\Word')
         ) {
-            $iWordID = $aSearchTerm['word_id'];
-            if (sizeof($this->aName)) {
-                if (($sPhraseType == '' || !$bFirstPhrase)
-                    && $sPhraseType != 'country'
-                    && !$bHasPartial
-                ) {
+            $iWordID = $oSearchTerm->iId;
+            // Full words can only be a name if they appear at the beginning
+            // of the phrase. In structured search the name must forcably in
+            // the first phrase. In unstructured search it may be in a later
+            // phrase when the first phrase is a house number.
+            if (!empty($this->aName) || !($bFirstPhrase || $sPhraseType == '')) {
+                if (($sPhraseType == '' || !$bFirstPhrase) && !$bHasPartial) {
                     $oSearch = clone $this;
-                    $oSearch->iSearchRank++;
+                    $oSearch->iSearchRank += 2;
                     $oSearch->aAddress[$iWordID] = $iWordID;
                     $aNewSearches[] = $oSearch;
                 } else {
@@ -289,6 +298,11 @@ class SearchDescription
                 $oSearch = clone $this;
                 $oSearch->iSearchRank++;
                 $oSearch->aName = array($iWordID => $iWordID);
+                if (CONST_Search_NameOnlySearchFrequencyThreshold) {
+                    $oSearch->bRareName =
+                        $oSearchTerm->iSearchNameCount
+                          < CONST_Search_NameOnlySearchFrequencyThreshold;
+                }
                 $aNewSearches[] = $oSearch;
             }
         }
@@ -299,7 +313,8 @@ class SearchDescription
     /**
      * Derive new searches by adding a partial term to the existing search.
      *
-     * @param mixed[] $aSearchTerm        Description of the token.
+     * @param string  $sToken             Term for the token.
+     * @param object  $oSearchTerm        Description of the token.
      * @param bool    $bStructuredPhrases True if the search is structured.
      * @param integer $iPhrase            Number of the phrase the token is in.
      * @param array[] $aFullTokens        List of full term tokens with the
@@ -307,46 +322,44 @@ class SearchDescription
      *
      * @return SearchDescription[] List of derived search descriptions.
      */
-    public function extendWithPartialTerm($aSearchTerm, $bStructuredPhrases, $iPhrase, $aFullTokens)
+    public function extendWithPartialTerm($sToken, $oSearchTerm, $bStructuredPhrases, $iPhrase, $aFullTokens)
     {
         // Only allow name terms.
-        if (!(isset($aSearchTerm['word_id']) && $aSearchTerm['word_id'])) {
+        if (!(is_a($oSearchTerm, '\Nominatim\Token\Word'))) {
             return array();
         }
 
         $aNewSearches = array();
-        $iWordID = $aSearchTerm['word_id'];
+        $iWordID = $oSearchTerm->iId;
 
         if ((!$bStructuredPhrases || $iPhrase > 0)
-            && sizeof($this->aName)
-            && strpos($aSearchTerm['word_token'], ' ') === false
+            && (!empty($this->aName))
+            && strpos($sToken, ' ') === false
         ) {
-            if ($aSearchTerm['search_name_count'] + 1 < CONST_Max_Word_Frequency) {
+            if ($oSearchTerm->iSearchNameCount < CONST_Max_Word_Frequency) {
                 $oSearch = clone $this;
-                $oSearch->iSearchRank++;
+                $oSearch->iSearchRank += 2;
                 $oSearch->aAddress[$iWordID] = $iWordID;
                 $aNewSearches[] = $oSearch;
             } else {
                 $oSearch = clone $this;
                 $oSearch->iSearchRank++;
                 $oSearch->aAddressNonSearch[$iWordID] = $iWordID;
-                if (preg_match('#^[0-9]+$#', $aSearchTerm['word_token'])) {
+                if (preg_match('#^[0-9]+$#', $sToken)) {
                     $oSearch->iSearchRank += 2;
                 }
-                if (sizeof($aFullTokens)) {
+                if (!empty($aFullTokens)) {
                     $oSearch->iSearchRank++;
                 }
                 $aNewSearches[] = $oSearch;
 
                 // revert to the token version?
-                foreach ($aFullTokens as $aSearchTermToken) {
-                    if (empty($aSearchTermToken['country_code'])
-                        && empty($aSearchTermToken['lat'])
-                        && empty($aSearchTermToken['class'])
-                    ) {
+                foreach ($aFullTokens as $oSearchTermToken) {
+                    if (is_a($oSearchTermToken, '\Nominatim\Token\Word')) {
                         $oSearch = clone $this;
                         $oSearch->iSearchRank++;
-                        $oSearch->aAddress[$aSearchTermToken['word_id']] = $aSearchTermToken['word_id'];
+                        $oSearch->aAddress[$oSearchTermToken->iId]
+                            = $oSearchTermToken->iId;
                         $aNewSearches[] = $oSearch;
                     }
                 }
@@ -354,17 +367,26 @@ class SearchDescription
         }
 
         if ((!$this->sPostcode && !$this->aAddress && !$this->aAddressNonSearch)
-            && (!sizeof($this->aName) || $this->iNamePhrase == $iPhrase)
+            && (empty($this->aName) || $this->iNamePhrase == $iPhrase)
         ) {
             $oSearch = clone $this;
-            $oSearch->iSearchRank++;
-            if (!sizeof($this->aName)) {
+            $oSearch->iSearchRank += 2;
+            if (empty($this->aName)) {
                 $oSearch->iSearchRank += 1;
             }
-            if (preg_match('#^[0-9]+$#', $aSearchTerm['word_token'])) {
+            if (preg_match('#^[0-9]+$#', $sToken)) {
                 $oSearch->iSearchRank += 2;
             }
-            if ($aSearchTerm['search_name_count'] + 1 < CONST_Max_Word_Frequency) {
+            if ($oSearchTerm->iSearchNameCount < CONST_Max_Word_Frequency) {
+                if (empty($this->aName)
+                    && CONST_Search_NameOnlySearchFrequencyThreshold
+                ) {
+                    $oSearch->bRareName =
+                        $oSearchTerm->iSearchNameCount
+                          < CONST_Search_NameOnlySearchFrequencyThreshold;
+                } else {
+                    $oSearch->bRareName = false;
+                }
                 $oSearch->aName[$iWordID] = $iWordID;
             } else {
                 $oSearch->aNameNonSearch[$iWordID] = $iWordID;
@@ -382,26 +404,22 @@ class SearchDescription
     /**
      * Query database for places that match this search.
      *
-     * @param object  $oDB                  Database connection to use.
-     * @param mixed[] $aWordFrequencyScores Number of times tokens appears
-     *                                      overall in a planet database.
-     * @param integer $iMinRank             Minimum address rank to restrict
-     *                                      search to.
-     * @param integer $iMaxRank             Maximum address rank to restrict
-     *                                      search to.
-     * @param integer $iLimit               Maximum number of results.
+     * @param object  $oDB      Nominatim::DB instance to use.
+     * @param integer $iMinRank Minimum address rank to restrict search to.
+     * @param integer $iMaxRank Maximum address rank to restrict search to.
+     * @param integer $iLimit   Maximum number of results.
      *
      * @return mixed[] An array with two fields: IDs contains the list of
      *                 matching place IDs and houseNumber the houseNumber
      *                 if appicable or -1 if not.
      */
-    public function query(&$oDB, &$aWordFrequencyScores, $iMinRank, $iMaxRank, $iLimit)
+    public function query(&$oDB, $iMinRank, $iMaxRank, $iLimit)
     {
         $aResults = array();
         $iHousenumber = -1;
 
         if ($this->sCountryCode
-            && !sizeof($this->aName)
+            && empty($this->aName)
             && !$this->iOperator
             && !$this->sClass
             && !$this->oContext->hasNearPoint()
@@ -410,7 +428,7 @@ class SearchDescription
             if (4 >= $iMinRank && 4 <= $iMaxRank) {
                 $aResults = $this->queryCountry($oDB);
             }
-        } elseif (!sizeof($this->aName) && !sizeof($this->aAddress)) {
+        } elseif (empty($this->aName) && empty($this->aAddress)) {
             // Neither name nor address? Then we must be
             // looking for a POI in a geographic area.
             if ($this->oContext->isBoundedSearch()) {
@@ -424,50 +442,47 @@ class SearchDescription
             // First search for places according to name and address.
             $aResults = $this->queryNamedPlace(
                 $oDB,
-                $aWordFrequencyScores,
                 $iMinRank,
                 $iMaxRank,
                 $iLimit
             );
 
-            //now search for housenumber, if housenumber provided
-            if ($this->sHouseNumber && sizeof($aResults)) {
-                $aNamedPlaceIDs = $aResults;
-                $aResults = $this->queryHouseNumber($oDB, $aNamedPlaceIDs, $iLimit);
+            // Now search for housenumber, if housenumber provided. Can be zero.
+            if (($this->sHouseNumber || $this->sHouseNumber === '0') && !empty($aResults)) {
+                // Downgrade the rank of the street results, they are missing
+                // the housenumber.
+                foreach ($aResults as $oRes) {
+                    $oRes->iResultRank++;
+                }
+
+                $aHnResults = $this->queryHouseNumber($oDB, $aResults);
 
-                if (!sizeof($aResults) && $this->looksLikeFullAddress()) {
-                    $aResults = $aNamedPlaceIDs;
+                if (!empty($aHnResults)) {
+                    foreach ($aHnResults as $oRes) {
+                        $aResults[$oRes->iId] = $oRes;
+                    }
                 }
             }
 
             // finally get POIs if requested
-            if ($this->sClass && sizeof($aResults)) {
+            if ($this->sClass && !empty($aResults)) {
                 $aResults = $this->queryPoiByOperator($oDB, $aResults, $iLimit);
             }
         }
 
-        if (CONST_Debug) {
-            echo "<br><b>Place IDs:</b> ";
-            var_dump(array_keys($aResults));
-        }
+        Debug::printDebugTable('Place IDs', $aResults);
 
-        if (sizeof($aResults) && $this->sPostcode) {
+        if (!empty($aResults) && $this->sPostcode) {
             $sPlaceIds = Result::joinIdsByTable($aResults, Result::TABLE_PLACEX);
             if ($sPlaceIds) {
                 $sSQL = 'SELECT place_id FROM placex';
                 $sSQL .= ' WHERE place_id in ('.$sPlaceIds.')';
-                $sSQL .= " AND postcode = '".$this->sPostcode."'";
-                if (CONST_Debug) var_dump($sSQL);
-                $aFilteredPlaceIDs = chksql($oDB->getCol($sSQL));
+                $sSQL .= " AND postcode != '".$this->sPostcode."'";
+                Debug::printSQL($sSQL);
+                $aFilteredPlaceIDs = $oDB->getCol($sSQL);
                 if ($aFilteredPlaceIDs) {
-                    $aNewResults = array();
                     foreach ($aFilteredPlaceIDs as $iPlaceId) {
-                        $aNewResults[$iPlaceId] = $aResults[$iPLaceId];
-                    }
-                    $aResults = $aNewResults;
-                    if (CONST_Debug) {
-                        echo "<br><b>Place IDs after postcode filtering:</b> ";
-                        var_dump(array_keys($aResults));
+                        $aResults[$iPlaceId]->iResultRank++;
                     }
                 }
             }
@@ -485,12 +500,14 @@ class SearchDescription
         if ($this->oContext->bViewboxBounded) {
             $sSQL .= ' AND ST_Intersects('.$this->oContext->sqlViewboxSmall.', geometry)';
         }
-        $sSQL .= " ORDER BY st_area(geometry) DESC LIMIT 1";
+        $sSQL .= ' ORDER BY st_area(geometry) DESC LIMIT 1';
+
+        Debug::printSQL($sSQL);
 
-        if (CONST_Debug) var_dump($sSQL);
+        $iPlaceId = $oDB->getOne($sSQL);
 
         $aResults = array();
-        foreach (chksql($oDB->getCol($sSQL)) as $iPlaceId) {
+        if ($iPlaceId) {
             $aResults[$iPlaceId] = new Result($iPlaceId);
         }
 
@@ -506,8 +523,7 @@ class SearchDescription
         $aDBResults = array();
         $sPoiTable = $this->poiTable();
 
-        $sSQL = 'SELECT count(*) FROM pg_tables WHERE tablename = \''.$sPoiTable."'";
-        if (chksql($oDB->getOne($sSQL))) {
+        if ($oDB->tableExists($sPoiTable)) {
             $sSQL = 'SELECT place_id FROM '.$sPoiTable.' ct';
             if ($this->oContext->sqlCountryList) {
                 $sSQL .= ' JOIN placex USING (place_id)';
@@ -527,23 +543,26 @@ class SearchDescription
             } elseif ($this->oContext->hasNearPoint()) {
                 $sSQL .= ' ORDER BY '.$this->oContext->distanceSQL('ct.centroid').' ASC';
             }
-            $sSQL .= " limit $iLimit";
-            if (CONST_Debug) var_dump($sSQL);
-            $aDBResults = chksql($oDB->getCol($sSQL));
+            $sSQL .= " LIMIT $iLimit";
+            Debug::printSQL($sSQL);
+            $aDBResults = $oDB->getCol($sSQL);
         }
 
         if ($this->oContext->hasNearPoint()) {
             $sSQL = 'SELECT place_id FROM placex WHERE ';
-            $sSQL .= 'class=\''.$this->sClass."' and type='".$this->sType."'";
+            $sSQL .= 'class = :class and type = :type';
             $sSQL .= ' AND '.$this->oContext->withinSQL('geometry');
             $sSQL .= ' AND linked_place_id is null';
             if ($this->oContext->sqlCountryList) {
                 $sSQL .= ' AND country_code in '.$this->oContext->sqlCountryList;
             }
-            $sSQL .= ' ORDER BY '.$this->oContext->distanceSQL('centroid')." ASC";
+            $sSQL .= ' ORDER BY '.$this->oContext->distanceSQL('centroid').' ASC';
             $sSQL .= " LIMIT $iLimit";
-            if (CONST_Debug) var_dump($sSQL);
-            $aDBResults = chksql($oDB->getCol($sSQL));
+            Debug::printSQL($sSQL);
+            $aDBResults = $oDB->getCol(
+                $sSQL,
+                array(':class' => $this->sClass, ':type' => $this->sType)
+            );
         }
 
         $aResults = array();
@@ -558,36 +577,43 @@ class SearchDescription
     {
         $sSQL = 'SELECT p.place_id FROM location_postcode p ';
 
-        if (sizeof($this->aAddress)) {
+        if (!empty($this->aAddress)) {
             $sSQL .= ', search_name s ';
             $sSQL .= 'WHERE s.place_id = p.parent_place_id ';
             $sSQL .= 'AND array_cat(s.nameaddress_vector, s.name_vector)';
-            $sSQL .= '      @> '.getArraySQL($this->aAddress).' AND ';
+            $sSQL .= '      @> '.$oDB->getArraySQL($this->aAddress).' AND ';
         } else {
             $sSQL .= 'WHERE ';
         }
 
         $sSQL .= "p.postcode = '".reset($this->aName)."'";
         $sSQL .= $this->countryCodeSQL(' AND p.country_code');
+        if ($this->oContext->bViewboxBounded) {
+            $sSQL .= ' AND ST_Intersects('.$this->oContext->sqlViewboxSmall.', geometry)';
+        }
         $sSQL .= $this->oContext->excludeSQL(' AND p.place_id');
         $sSQL .= " LIMIT $iLimit";
 
-        if (CONST_Debug) var_dump($sSQL);
+        Debug::printSQL($sSQL);
 
         $aResults = array();
-        foreach (chksql($oDB->getCol($sSQL)) as $iPlaceId) {
+        foreach ($oDB->getCol($sSQL) as $iPlaceId) {
             $aResults[$iPlaceId] = new Result($iPlaceId, Result::TABLE_POSTCODE);
         }
 
         return $aResults;
     }
 
-    private function queryNamedPlace(&$oDB, $aWordFrequencyScores, $iMinAddressRank, $iMaxAddressRank, $iLimit)
+    private function queryNamedPlace(&$oDB, $iMinAddressRank, $iMaxAddressRank, $iLimit)
     {
         $aTerms = array();
         $aOrder = array();
 
-        if ($this->sHouseNumber && sizeof($this->aAddress)) {
+        // Sort by existence of the requested house number but only if not
+        // too many results are expected for the street, i.e. if the result
+        // will be narrowed down by an address. Remeber that with ordering
+        // every single result has to be checked.
+        if ($this->sHouseNumber && (!empty($this->aAddress) || $this->sPostcode)) {
             $sHouseNumberRegex = '\\\\m'.$this->sHouseNumber.'\\\\M';
             $aOrder[] = ' (';
             $aOrder[0] .= 'EXISTS(';
@@ -613,19 +639,15 @@ class SearchDescription
             $aOrder[0] .= ') DESC';
         }
 
-        if (sizeof($this->aName)) {
-            $aTerms[] = 'name_vector @> '.getArraySQL($this->aName);
+        if (!empty($this->aName)) {
+            $aTerms[] = 'name_vector @> '.$oDB->getArraySQL($this->aName);
         }
-        if (sizeof($this->aAddress)) {
+        if (!empty($this->aAddress)) {
             // For infrequent name terms disable index usage for address
-            if (CONST_Search_NameOnlySearchFrequencyThreshold
-                && sizeof($this->aName) == 1
-                && $aWordFrequencyScores[$this->aName[reset($this->aName)]]
-                     < CONST_Search_NameOnlySearchFrequencyThreshold
-            ) {
-                $aTerms[] = 'array_cat(nameaddress_vector,ARRAY[]::integer[]) @> '.getArraySQL($this->aAddress);
+            if ($this->bRareName) {
+                $aTerms[] = 'array_cat(nameaddress_vector,ARRAY[]::integer[]) @> '.$oDB->getArraySQL($this->aAddress);
             } else {
-                $aTerms[] = 'nameaddress_vector @> '.getArraySQL($this->aAddress);
+                $aTerms[] = 'nameaddress_vector @> '.$oDB->getArraySQL($this->aAddress);
             }
         }
 
@@ -635,13 +657,13 @@ class SearchDescription
         }
 
         if ($this->sHouseNumber) {
-            $aTerms[] = "address_rank between 16 and 27";
+            $aTerms[] = 'address_rank between 16 and 27';
         } elseif (!$this->sClass || $this->iOperator == Operator::NAME) {
             if ($iMinAddressRank > 0) {
-                $aTerms[] = "address_rank >= ".$iMinAddressRank;
+                $aTerms[] = 'address_rank >= '.$iMinAddressRank;
             }
             if ($iMaxAddressRank < 30) {
-                $aTerms[] = "address_rank <= ".$iMaxAddressRank;
+                $aTerms[] = 'address_rank <= '.$iMaxAddressRank;
             }
         }
 
@@ -649,7 +671,7 @@ class SearchDescription
             $aTerms[] = $this->oContext->withinSQL('centroid');
             $aOrder[] = $this->oContext->distanceSQL('centroid');
         } elseif ($this->sPostcode) {
-            if (!sizeof($this->aAddress)) {
+            if (empty($this->aAddress)) {
                 $aTerms[] = "EXISTS(SELECT place_id FROM location_postcode p WHERE p.postcode = '".$this->sPostcode."' AND ST_DWithin(search_name.centroid, p.geometry, 0.1))";
             } else {
                 $aOrder[] = "(SELECT min(ST_Distance(search_name.centroid, p.geometry)) FROM location_postcode p WHERE p.postcode = '".$this->sPostcode."')";
@@ -672,15 +694,15 @@ class SearchDescription
         if ($this->sHouseNumber) {
             $sImportanceSQL = '- abs(26 - address_rank) + 3';
         } else {
-            $sImportanceSQL = '(CASE WHEN importance = 0 OR importance IS NULL THEN 0.75-(search_rank::float/40) ELSE importance END)';
+            $sImportanceSQL = '(CASE WHEN importance = 0 OR importance IS NULL THEN 0.75001-(search_rank::float/40) ELSE importance END)';
         }
         $sImportanceSQL .= $this->oContext->viewboxImportanceSQL('centroid');
         $aOrder[] = "$sImportanceSQL DESC";
 
-        if (sizeof($this->aFullNameAddress)) {
+        if (!empty($this->aFullNameAddress)) {
             $sExactMatchSQL = ' ( ';
             $sExactMatchSQL .= ' SELECT count(*) FROM ( ';
-            $sExactMatchSQL .= '  SELECT unnest('.getArraySQL($this->aFullNameAddress).')';
+            $sExactMatchSQL .= '  SELECT unnest('.$oDB->getArraySQL($this->aFullNameAddress).')';
             $sExactMatchSQL .= '    INTERSECT ';
             $sExactMatchSQL .= '  SELECT unnest(nameaddress_vector)';
             $sExactMatchSQL .= ' ) s';
@@ -691,24 +713,21 @@ class SearchDescription
         }
 
         if ($this->sHouseNumber || $this->sClass) {
-            $iLimit = 20;
+            $iLimit = 40;
         }
 
         $aResults = array();
 
-        if (sizeof($aTerms)) {
+        if (!empty($aTerms)) {
             $sSQL = 'SELECT place_id,'.$sExactMatchSQL;
             $sSQL .= ' FROM search_name';
             $sSQL .= ' WHERE '.join(' and ', $aTerms);
             $sSQL .= ' ORDER BY '.join(', ', $aOrder);
             $sSQL .= ' LIMIT '.$iLimit;
 
-            if (CONST_Debug) var_dump($sSQL);
+            Debug::printSQL($sSQL);
 
-            $aDBResults = chksql(
-                $oDB->getAll($sSQL),
-                "Could not get places for search terms."
-            );
+            $aDBResults = $oDB->getAll($sSQL, null, 'Could not get places for search terms.');
 
             foreach ($aDBResults as $aResult) {
                 $oResult = new Result($aResult['place_id']);
@@ -720,7 +739,7 @@ class SearchDescription
         return $aResults;
     }
 
-    private function queryHouseNumber(&$oDB, $aRoadPlaceIDs, $iLimit)
+    private function queryHouseNumber(&$oDB, $aRoadPlaceIDs)
     {
         $aResults = array();
         $sPlaceIDs = Result::joinIdsByTable($aRoadPlaceIDs, Result::TABLE_PLACEX);
@@ -734,18 +753,17 @@ class SearchDescription
         $sSQL .= 'WHERE parent_place_id in ('.$sPlaceIDs.')';
         $sSQL .= "  AND transliteration(housenumber) ~* E'".$sHouseNumberRegex."'";
         $sSQL .= $this->oContext->excludeSQL(' AND place_id');
-        $sSQL .= " LIMIT $iLimit";
 
-        if (CONST_Debug) var_dump($sSQL);
+        Debug::printSQL($sSQL);
 
         // XXX should inherit the exactMatches from its parent
-        foreach (chksql($oDB->getCol($sSQL)) as $iPlaceId) {
+        foreach ($oDB->getCol($sSQL) as $iPlaceId) {
             $aResults[$iPlaceId] = new Result($iPlaceId);
         }
 
         $bIsIntHouseNumber= (bool) preg_match('/[0-9]+/', $this->sHouseNumber);
         $iHousenumber = intval($this->sHouseNumber);
-        if ($bIsIntHouseNumber && !sizeof($aResults)) {
+        if ($bIsIntHouseNumber && empty($aResults)) {
             // if nothing found, search in the interpolation line table
             $sSQL = 'SELECT distinct place_id FROM location_property_osmline';
             $sSQL .= ' WHERE startnumber is not NULL';
@@ -759,14 +777,13 @@ class SearchDescription
                 $sSQL .= "interpolationtype='odd'";
             }
             $sSQL .= " or interpolationtype='all') and ";
-            $sSQL .= $iHousenumber.">=startnumber and ";
-            $sSQL .= $iHousenumber."<=endnumber";
+            $sSQL .= $iHousenumber.'>=startnumber and ';
+            $sSQL .= $iHousenumber.'<=endnumber';
             $sSQL .= $this->oContext->excludeSQL(' AND place_id');
-            $sSQL .= " limit $iLimit";
 
-            if (CONST_Debug) var_dump($sSQL);
+            Debug::printSQL($sSQL);
 
-            foreach (chksql($oDB->getCol($sSQL)) as $iPlaceId) {
+            foreach ($oDB->getCol($sSQL) as $iPlaceId) {
                 $oResult = new Result($iPlaceId, Result::TABLE_OSMLINE);
                 $oResult->iHouseNumber = $iHousenumber;
                 $aResults[$iPlaceId] = $oResult;
@@ -774,22 +791,21 @@ class SearchDescription
         }
 
         // If nothing found try the aux fallback table
-        if (CONST_Use_Aux_Location_data && !sizeof($aResults)) {
+        if (CONST_Use_Aux_Location_data && empty($aResults)) {
             $sSQL = 'SELECT place_id FROM location_property_aux';
             $sSQL .= ' WHERE parent_place_id in ('.$sPlaceIDs.')';
             $sSQL .= " AND housenumber = '".$this->sHouseNumber."'";
             $sSQL .= $this->oContext->excludeSQL(' AND place_id');
-            $sSQL .= " limit $iLimit";
 
-            if (CONST_Debug) var_dump($sSQL);
+            Debug::printSQL($sSQL);
 
-            foreach (chksql($oDB->getCol($sSQL)) as $iPlaceId) {
+            foreach ($oDB->getCol($sSQL) as $iPlaceId) {
                 $aResults[$iPlaceId] = new Result($iPlaceId, Result::TABLE_AUX);
             }
         }
 
         // If nothing found then search in Tiger data (location_property_tiger)
-        if (CONST_Use_US_Tiger_Data && $bIsIntHouseNumber && !sizeof($aResults)) {
+        if (CONST_Use_US_Tiger_Data && $bIsIntHouseNumber && empty($aResults)) {
             $sSQL = 'SELECT place_id FROM location_property_tiger';
             $sSQL .= ' WHERE parent_place_id in ('.$sPlaceIDs.') and (';
             if ($iHousenumber % 2 == 0) {
@@ -798,14 +814,13 @@ class SearchDescription
                 $sSQL .= "interpolationtype='odd'";
             }
             $sSQL .= " or interpolationtype='all') and ";
-            $sSQL .= $iHousenumber.">=startnumber and ";
-            $sSQL .= $iHousenumber."<=endnumber";
+            $sSQL .= $iHousenumber.'>=startnumber and ';
+            $sSQL .= $iHousenumber.'<=endnumber';
             $sSQL .= $this->oContext->excludeSQL(' AND place_id');
-            $sSQL .= " limit $iLimit";
 
-            if (CONST_Debug) var_dump($sSQL);
+            Debug::printSQL($sSQL);
 
-            foreach (chksql($oDB->getCol($sSQL)) as $iPlaceId) {
+            foreach ($oDB->getCol($sSQL) as $iPlaceId) {
                 $oResult = new Result($iPlaceId, Result::TABLE_TIGER);
                 $oResult->iHouseNumber = $iHousenumber;
                 $aResults[$iPlaceId] = $oResult;
@@ -832,14 +847,14 @@ class SearchDescription
             $sSQL .= " WHERE place_id in ($sPlaceIDs)";
             $sSQL .= "   AND class='".$this->sClass."' ";
             $sSQL .= "   AND type='".$this->sType."'";
-            $sSQL .= "   AND linked_place_id is null";
+            $sSQL .= '   AND linked_place_id is null';
             $sSQL .= $this->oContext->excludeSQL(' AND place_id');
-            $sSQL .= " ORDER BY rank_search ASC ";
+            $sSQL .= ' ORDER BY rank_search ASC ';
             $sSQL .= " LIMIT $iLimit";
 
-            if (CONST_Debug) var_dump($sSQL);
+            Debug::printSQL($sSQL);
 
-            foreach (chksql($oDB->getCol($sSQL)) as $iPlaceId) {
+            foreach ($oDB->getCol($sSQL) as $iPlaceId) {
                 $aResults[$iPlaceId] = new Result($iPlaceId);
             }
         }
@@ -847,12 +862,11 @@ class SearchDescription
         // NEAR and IN are handled the same
         if ($this->iOperator == Operator::TYPE || $this->iOperator == Operator::NEAR) {
             $sClassTable = $this->poiTable();
-            $sSQL = "SELECT count(*) FROM pg_tables WHERE tablename = '$sClassTable'";
-            $bCacheTable = (bool) chksql($oDB->getOne($sSQL));
+            $bCacheTable = $oDB->tableExists($sClassTable);
 
             $sSQL = "SELECT min(rank_search) FROM placex WHERE place_id in ($sPlaceIDs)";
-            if (CONST_Debug) var_dump($sSQL);
-            $iMaxRank = (int)chksql($oDB->getOne($sSQL));
+            Debug::printSQL($sSQL);
+            $iMaxRank = (int) $oDB->getOne($sSQL);
 
             // For state / country level searches the normal radius search doesn't work very well
             $sPlaceGeom = false;
@@ -862,10 +876,10 @@ class SearchDescription
                 $sSQL .= " WHERE place_id in ($sPlaceIDs)";
                 $sSQL .= "   AND rank_search < $iMaxRank + 5";
                 $sSQL .= "   AND ST_GeometryType(geometry) in ('ST_Polygon','ST_MultiPolygon')";
-                $sSQL .= " ORDER BY rank_search ASC ";
-                $sSQL .= " LIMIT 1";
-                if (CONST_Debug) var_dump($sSQL);
-                $sPlaceGeom = chksql($oDB->getOne($sSQL));
+                $sSQL .= ' ORDER BY rank_search ASC ';
+                $sSQL .= ' LIMIT 1';
+                Debug::printSQL($sSQL);
+                $sPlaceGeom = $oDB->getOne($sSQL);
             }
 
             if ($sPlaceGeom) {
@@ -874,8 +888,8 @@ class SearchDescription
                 $iMaxRank += 5;
                 $sSQL = 'SELECT place_id FROM placex';
                 $sSQL .= " WHERE place_id in ($sPlaceIDs) and rank_search < $iMaxRank";
-                if (CONST_Debug) var_dump($sSQL);
-                $aPlaceIDs = chksql($oDB->getCol($sSQL));
+                Debug::printSQL($sSQL);
+                $aPlaceIDs = $oDB->getCol($sSQL);
                 $sPlaceIDs = join(',', $aPlaceIDs);
             }
 
@@ -889,7 +903,7 @@ class SearchDescription
                     if ($this->oContext->hasNearPoint()) {
                         $sOrderBySQL = $this->oContext->distanceSQL('l.centroid');
                     } elseif ($sPlaceIDs) {
-                        $sOrderBySQL = "ST_Distance(l.centroid, f.geometry)";
+                        $sOrderBySQL = 'ST_Distance(l.centroid, f.geometry)';
                     } elseif ($sPlaceGeom) {
                         $sOrderBySQL = "ST_Distance(st_centroid('".$sPlaceGeom."'), l.centroid)";
                     }
@@ -905,7 +919,7 @@ class SearchDescription
                     $sSQL .= ' from '.$sClassTable.' as l';
 
                     if ($sPlaceIDs) {
-                        $sSQL .= ",placex as f WHERE ";
+                        $sSQL .= ',placex as f WHERE ';
                         $sSQL .= "f.place_id in ($sPlaceIDs) ";
                         $sSQL .= " AND ST_DWithin(l.centroid, f.centroid, $fRange)";
                     } elseif ($sPlaceGeom) {
@@ -919,9 +933,9 @@ class SearchDescription
                     }
                     $sSQL .= " limit $iLimit";
 
-                    if (CONST_Debug) var_dump($sSQL);
+                    Debug::printSQL($sSQL);
 
-                    foreach (chksql($oDB->getCol($sSQL)) as $iPlaceId) {
+                    foreach ($oDB->getCol($sSQL) as $iPlaceId) {
                         $aResults[$iPlaceId] = new Result($iPlaceId);
                     }
                 } else {
@@ -933,7 +947,7 @@ class SearchDescription
                     if ($this->oContext->hasNearPoint()) {
                         $sOrderBySQL = $this->oContext->distanceSQL('l.geometry');
                     } else {
-                        $sOrderBySQL = "ST_Distance(l.geometry, f.geometry)";
+                        $sOrderBySQL = 'ST_Distance(l.geometry, f.geometry)';
                     }
 
                     $sSQL = 'SELECT distinct l.place_id';
@@ -947,13 +961,13 @@ class SearchDescription
                     $sSQL .= "  AND l.type='".$this->sType."'";
                     $sSQL .= $this->oContext->excludeSQL(' AND l.place_id');
                     if ($sOrderBySQL) {
-                        $sSQL .= "ORDER BY orderterm ASC";
+                        $sSQL .= 'ORDER BY orderterm ASC';
                     }
                     $sSQL .= " limit $iLimit";
 
-                    if (CONST_Debug) var_dump($sSQL);
+                    Debug::printSQL($sSQL);
 
-                    foreach (chksql($oDB->getCol($sSQL)) as $iPlaceId) {
+                    foreach ($oDB->getCol($sSQL) as $iPlaceId) {
                         $aResults[$iPlaceId] = new Result($iPlaceId);
                     }
                 }
@@ -996,25 +1010,43 @@ class SearchDescription
     //////////// Debugging functions
 
 
+    public function debugInfo()
+    {
+        return array(
+                'Search rank' => $this->iSearchRank,
+                'Country code' => $this->sCountryCode,
+                'Name terms' => $this->aName,
+                'Name terms (stop words)' => $this->aNameNonSearch,
+                'Address terms' => $this->aAddress,
+                'Address terms (stop words)' => $this->aAddressNonSearch,
+                'Address terms (full words)' => $this->aFullNameAddress,
+                'Special search' => $this->iOperator,
+                'Class' => $this->sClass,
+                'Type' => $this->sType,
+                'House number' => $this->sHouseNumber,
+                'Postcode' => $this->sPostcode
+               );
+    }
+
     public function dumpAsHtmlTableRow(&$aWordIDs)
     {
         $kf = function ($k) use (&$aWordIDs) {
             return $aWordIDs[$k];
         };
 
-        echo "<tr>";
+        echo '<tr>';
         echo "<td>$this->iSearchRank</td>";
-        echo "<td>".join(', ', array_map($kf, $this->aName))."</td>";
-        echo "<td>".join(', ', array_map($kf, $this->aNameNonSearch))."</td>";
-        echo "<td>".join(', ', array_map($kf, $this->aAddress))."</td>";
-        echo "<td>".join(', ', array_map($kf, $this->aAddressNonSearch))."</td>";
-        echo "<td>".$this->sCountryCode."</td>";
-        echo "<td>".Operator::toString($this->iOperator)."</td>";
-        echo "<td>".$this->sClass."</td>";
-        echo "<td>".$this->sType."</td>";
-        echo "<td>".$this->sPostcode."</td>";
-        echo "<td>".$this->sHouseNumber."</td>";
-
-        echo "</tr>";
+        echo '<td>'.join(', ', array_map($kf, $this->aName)).'</td>';
+        echo '<td>'.join(', ', array_map($kf, $this->aNameNonSearch)).'</td>';
+        echo '<td>'.join(', ', array_map($kf, $this->aAddress)).'</td>';
+        echo '<td>'.join(', ', array_map($kf, $this->aAddressNonSearch)).'</td>';
+        echo '<td>'.$this->sCountryCode.'</td>';
+        echo '<td>'.Operator::toString($this->iOperator).'</td>';
+        echo '<td>'.$this->sClass.'</td>';
+        echo '<td>'.$this->sType.'</td>';
+        echo '<td>'.$this->sPostcode.'</td>';
+        echo '<td>'.$this->sHouseNumber.'</td>';
+
+        echo '</tr>';
     }
 }