KTS-4214. Changed the behaviour of the search to allow multiple joins on a singl…

…e table when the document_fields_link table is involved - i.e. an AnyMetadata search. Fixed Search does not return any results if more than one metadata type is included in the search expression with an AND statement. Committed by: Paul Barrett Reviewed by: Megan Watson

KTS-4214. Changed the behaviour of the search to allow multiple joins on a singl…
…e table when the document_fields_link table is involved - i.e. an AnyMetadata search. Fixed Search does not return any results if more than one metadata type is included in the search expression with an AND statement. Committed by: Paul Barrett Reviewed by: Megan Watson
Paul Barrett
1 parent fc3b3458
Showing 2 changed files with 42 additions and 4 deletions
search2/search/expr.inc.php
search2/search/fields/AnyMetadataField.inc.php
@@ -1079,6 +1079,7 @@ class SQLQueryBuilder implements QueryBuilder
 		        if (array_key_exists($tablename, $this->used_tables))
 		        {
 		            $this->used_tables[$tablename]++;
+                    if (isset($expr->references)) ++$expr->references;
 		        }
 		    }
 		}
@@ -1244,7 +1245,18 @@ class SQLQueryBuilder implements QueryBuilder
             }
             if ($this->used_tables['document_fields_link'] > 0)
             {
-                $sql .= ' LEFT JOIN document_fields_link pdfl ON dmv.id=pdfl.metadata_version_id ' . "\n";
+                // NOTE this is a bit of a hack, maybe? or maybe it really is the best way?
+                // ...what about using the loop below which checks the expression
+                // for a join table rather than this up here? - otherwise this only
+                // affects this particular query type - then again maybe that's what we want...
+                for ($i = 0; $i < $this->used_tables['document_fields_link']; ++$i)
+                {
+                    if ($i > 0) $counter = $i;
+                    else $counter = '';
+
+                    $sql .= ' LEFT JOIN document_fields_link pdfl' . $counter . ' '
+                         .  'ON dmv.id=pdfl' . $counter . '.metadata_version_id ' . "\n";
+                }
             }
             if ($this->used_tables['tag_words'] > 0)
@@ -1374,7 +1386,6 @@ class SQLQueryBuilder implements QueryBuilder
 	public function buildComplexQuery($expr)
 	{
-//		print "building complex \n\n";
 		$this->exploreExprs($expr);
 		$sql = $this->buildCoreSQL();
@@ -1396,7 +1407,6 @@ class SQLQueryBuilder implements QueryBuilder
 	public function buildSimpleQuery($op, $group)
 	{
-//		print "building simple \n\n";
 		$this->exploreGroup($group);
         $sql = $this->buildCoreSQL();
@@ -40,7 +40,7 @@
 class AnyMetadataField extends DBFieldExpr
 {
 	public $general_op = ExprOp::CONTAINS;
-
+    public $references = 0;
     public function __construct()
     {
@@ -48,6 +48,34 @@ class AnyMetadataField extends DBFieldExpr
         $this->setAlias('Metadata');
     }
+    /*
+     * Overridden function to adjust table alias in cases of
+     * the document_fields_link table being included more than once
+     *
+     * NOTE this only works in conjunction with code in expr.inc.php which adds the left joins to the db query.
+     *      I don't like this and think we should look for a way to make the table joining more generic
+     *      such that it can be controlled via these classes and thereby contained as a unit.
+     */
+    public function modifyName($name)
+    {
+        if ($this->references > 0)
+        {
+            static $count = 0;
+            if ($count >= $this->references)
+            {
+                $count = 0;
+            }
+
+            if ((($pos = strpos($name, '.')) !== false) && ($count != 0))
+            {
+                $name = substr($name, 0, $pos) . $count . substr($name, $pos);
+            }
+            ++$count;
+        }
+
+    	return $name;
+    }
+
     public function getInputRequirements()
     {
         return array('value'=>array('type'=>FieldInputType::TEXT));