feature deleted: code for categories link was too complicated for such a

simple fature. Replaced by static association. Links are not persistent
anymore.

modification removed: #image_category.is_storage replaced by
#images.storage_category_id as in branche 1.5..


git-svn-id: http://piwigo.org/svn/trunk@1121 68402e56-0260-453c-a942-63ccdbb3a9ee

8 files changed, 161 insertions, 703 deletions

diff --git a/admin/cat_modify.php b/admin/cat_modify.php
index cfff0d31f..4f4617224 100644
--- a/admin/cat_modify.php
+++ b/admin/cat_modify.php
@@ -114,104 +114,50 @@ else if (isset($_POST['submitAdd']))
     array_push($page['infos'], $output_create['info']);
     
     // Link the new category to the current category
-    $query = '
-INSERT
-  INTO '.CATEGORIES_LINK_TABLE.'
-  (source, destination)
-  VALUES
-  ('.$_GET['cat_id'].', '.$output_create['id'].')
-;';
-    pwg_query($query);
+    associate_categories_to_categories(
+      array($_GET['cat_id']),
+      array($output_create['id'])
+      );
 
-    check_links(array($output_create['id']));
-    update_category(array($output_create['id']));
-  }
-}
-else if (isset($_POST['destination_trueify'])
-         and isset($_POST['destination_false'])
-         and count($_POST['destination_false']))
-{
-  $datas = array();
-  
-  foreach ($_POST['destination_false'] as $category_id)
-  {
+    // information
     array_push(
-      $datas,
-      array(
-        'source'      => $_GET['cat_id'],
-        'destination' => $category_id,
+      $page['infos'],
+      sprintf(
+        l10n('Category elements associated to the following categories: %s'),
+        '<ul><li>'
+        .get_cat_display_name_from_id($output_create['id'])
+        .'</li></ul>'
         )
       );
   }
-  
-  mass_inserts(
-    CATEGORIES_LINK_TABLE,
-    array('source', 'destination'),
-    $datas
-    );
-
-  check_links($_POST['destination_false']);
-  update_category(
-    $_POST['destination_false'],
-    true                          // recursive update
-    );
 }
-else if (isset($_POST['destination_falsify'])
-         and isset($_POST['destination_true'])
-         and count($_POST['destination_true']))
+else if (isset($_POST['submitDestinations'])
+         and isset($_POST['destinations'])
+         and count($_POST['destinations']) > 0)
 {
-  foreach ($_POST['destination_true'] as $destination)
-  {
-    delete_sources($destination, array($_GET['cat_id']));
-  }
-
-  update_category(
-    $_POST['destination_true'],
-    true                          // recursive update
+  associate_categories_to_categories(
+    array($_GET['cat_id']),
+    $_POST['destinations']
     );
-}
-else if (isset($_POST['source_trueify'])
-         and isset($_POST['source_false'])
-         and count($_POST['source_false']))
-{
-  $datas = array();
-  
-  foreach ($_POST['source_false'] as $category_id)
+
+  $category_names = array();
+  foreach ($_POST['destinations'] as $category_id)
   {
     array_push(
-      $datas,
-      array(
-        'source'      => $category_id,
-        'destination' => $_GET['cat_id'],
-        )
+      $category_names,
+      get_cat_display_name_from_id($category_id)
       );
   }
-  
-  mass_inserts(
-    CATEGORIES_LINK_TABLE,
-    array('source', 'destination'),
-    $datas
-    );
 
-  check_links(array($_GET['cat_id']));
-  update_category(
-    array($_GET['cat_id']),
-    true                          // recursive update
-    );
-}
-else if (isset($_POST['source_falsify'])
-         and isset($_POST['source_true'])
-         and count($_POST['source_true']))
-{
-  delete_sources($_GET['cat_id'], $_POST['source_true']);
-  
-  update_category(
-    array($_GET['cat_id']),
-    true                          // recursive update
+  array_push(
+    $page['infos'],
+    sprintf(
+      l10n('Category elements associated to the following categories: %s'),
+      '<ul><li>'.implode('</li><li>', $category_names).'</li></ul>'
+      )
     );
 }
 
-
 $query = '
 SELECT *
   FROM '.CATEGORIES_TABLE.'
@@ -381,7 +327,7 @@ SELECT tn_ext,path
   }
 }
 
-if (!$category['is_virtual']) //!empty($category['dir']))
+if (!$category['is_virtual'])
 {
   $template->assign_block_vars(
     'storage',
@@ -469,47 +415,17 @@ display_select_cat_wrapper(
 
 // destination categories
 $query = '
-SELECT DISTINCT id, name, uppercats, global_rank
-  FROM '.CATEGORIES_TABLE.'
-    INNER JOIN '.CATEGORIES_LINK_TABLE.' ON destination = id
-  WHERE source = '.$_GET['cat_id'].'
-;';
-display_select_cat_wrapper($query, array(), 'destination_option_true');
-
-// non destination categories
-$destinations = array_merge(
-  array($_GET['cat_id']),
-  array_from_query($query, 'id')
-  );
-
-$query = '
-SELECT DISTINCT id, name, uppercats, global_rank
-  FROM '.CATEGORIES_TABLE.'
-  WHERE id NOT IN ('.implode(',', $destinations).')
-;';
-display_select_cat_wrapper($query, array(), 'destination_option_false');
-
-// source categories
-$query = '
-SELECT DISTINCT id, name, uppercats, global_rank
+SELECT id,name,uppercats,global_rank
   FROM '.CATEGORIES_TABLE.'
-    INNER JOIN '.CATEGORIES_LINK_TABLE.' ON source = id
-  WHERE destination = '.$_GET['cat_id'].'
+  WHERE id != '.$category['id'].'
 ;';
-display_select_cat_wrapper($query, array(), 'source_option_true');
 
-// non source categories
-$sources = array_merge(
-  array($_GET['cat_id']),
-  array_from_query($query, 'id')
+display_select_cat_wrapper(
+  $query,
+  array(),
+  'category_option_destination'
   );
 
-$query = '
-SELECT DISTINCT id, name, uppercats, global_rank
-  FROM '.CATEGORIES_TABLE.'
-  WHERE id NOT IN ('.implode(',', $sources).')
-;';
-display_select_cat_wrapper($query, array(), 'source_option_false');
 
 //----------------------------------------------------------- sending html code
 $template->assign_var_from_handle('ADMIN_CONTENT', 'categories');
diff --git a/admin/element_set_global.php b/admin/element_set_global.php
index 22ea2df13..041cbe0cf 100644
--- a/admin/element_set_global.php
+++ b/admin/element_set_global.php
@@ -95,80 +95,35 @@ DELETE
 
   if ($_POST['associate'] != 0 and count($collection) > 0)
   {
-    $datas = array();
-
-    $query = '
-SELECT image_id
-  FROM '.IMAGE_CATEGORY_TABLE.'
-  WHERE category_id = '.$_POST['associate'].'
-;';
-    $associated = array_from_query($query, 'image_id');
-
-    $associable = array_diff($collection, $associated);
-
-    if (count($associable) != 0)
-    {
-      foreach ($associable as $item)
-      {
-        array_push(
-          $datas,
-          array(
-            'category_id' => $_POST['associate'],
-            'image_id' => $item
-            )
-          );
-      }
-
-      mass_inserts(
-        IMAGE_CATEGORY_TABLE,
-        array('image_id', 'category_id'),
-        $datas
-        );
-
-      check_links();
-      update_category(array($_POST['associate']));
-    }
+    associate_images_to_categories(
+      $collection,
+      array($_POST['associate'])
+      );
   }
 
   if ($_POST['dissociate'] != 0 and count($collection) > 0)
   {
-    // First, we must identify which elements in the collection are really
-    // virtually associated with the category
+    // physical links must not be broken, so we must first retrieve image_id
+    // which create virtual links with the category to "dissociate from".
     $query = '
-SELECT image_id
+SELECT id
   FROM '.IMAGE_CATEGORY_TABLE.'
+    INNER JOIN '.IMAGES_TABLE.' ON image_id = id
   WHERE category_id = '.$_POST['dissociate'].'
-    AND image_id IN ('.implode(',', $collection).')
-    AND is_storage = \'false\'
+    AND id IN ('.implode(',', $collection).')
+    AND category_id != storage_category_id
 ;';
-    $associated_images = array_from_query($query, 'image_id');
-
-    // If the same element is associated to a source and its destinations,
-    // dissociating the element with the source implies dissociating the
-    // element fwith the destination.
-    $destinations_of = get_destinations($_POST['dissociate']);
+    $dissociables = array_from_query($query, 'id');
 
-    $associated_categories = array_merge(
-      array($_POST['dissociate']),
-      $destinations_of[ $_POST['dissociate'] ]
-      );
-
-    // Eventually, deletion of associations
     $query = '
 DELETE
   FROM '.IMAGE_CATEGORY_TABLE.'
-  WHERE category_id IN ('.implode(',', $associated_categories).'
-    AND image_id IN ('.implode(',', $associated_images).')
+  WHERE category_id = '.$_POST['dissociate'].'
+    AND image_id IN ('.implode(',', $dissociables).')
 ';
     pwg_query($query);
-
-    // check source/destination links. If category C has for sources A and
-    // B, if picture 1 was associated to A and B, the previous code lines
-    // have deleted the link between C and 1, while it should be kept due to
-    // B. Who said "complicated"?
-    check_links();
-
-    update_category($associated_categories);
+    
+    update_category($_POST['dissociate']);
   }
 
   $datas = array();
@@ -318,7 +273,7 @@ SELECT DISTINCT(category_id) AS id, c.name, uppercats, global_rank
   WHERE ic.image_id IN ('.implode(',', $page['cat_elements_id']).')
     AND ic.category_id = c.id
     AND ic.image_id = i.id
-    AND ic.is_storage = \'false\'
+    AND ic.category_id != i.storage_category_id
 ;';
   display_select_cat_wrapper($query, array(), $blockname, true);
 }
diff --git a/admin/include/functions.php b/admin/include/functions.php
index 3a8c6b506..f9435b1f1 100644
--- a/admin/include/functions.php
+++ b/admin/include/functions.php
@@ -152,22 +152,16 @@ function delete_categories($ids)
 
   // destruction of all the related elements
   $query = '
-SELECT image_id
-  FROM '.IMAGE_CATEGORY_TABLE.'
-  WHERE is_storage = \'true\'
-    AND category_id IN ('.
-    wordwrap(
-      implode(', ', $ids),
-      80,
-      "\n"
-      ).
-    ')
+SELECT id
+  FROM '.IMAGES_TABLE.'
+  WHERE storage_category_id IN (
+'.wordwrap(implode(', ', $ids), 80, "\n").')
 ;';
   $result = pwg_query($query);
   $element_ids = array();
   while ($row = mysql_fetch_array($result))
   {
-    array_push($element_ids, $row['image_id']);
+    array_push($element_ids, $row['id']);
   }
   delete_elements($element_ids);
 
@@ -194,37 +188,6 @@ DELETE FROM '.GROUP_ACCESS_TABLE.'
 ;';
   pwg_query($query);
 
-  // source/destination links deletion
-  $query = '
-SELECT destination, source
-  FROM '.CATEGORIES_LINK_TABLE.'
-  WHERE source IN ('.implode(',', $ids).')
-    OR destination IN ('.implode(',', $ids).')
-;';
-  $result = pwg_query($query);
-
-  $sources_of = array();
-
-  while ($row = mysql_fetch_array($result))
-  {
-    if (!isset($sources_of[ $row['destination'] ]))
-    {
-      $sources_of[ $row['destination'] ] = array();
-    }
-
-    array_push(
-      $sources_of[ $row['destination'] ],
-      $row['source']
-      );
-  }
-
-  foreach ($sources_of as $destination => $sources)
-  {
-    delete_sources($destination, $sources);
-  }
-
-  update_category();
-
   // destruction of the category
   $query = '
 DELETE FROM '.CATEGORIES_TABLE.'
@@ -441,15 +404,14 @@ SELECT id
 SELECT category_id,
        COUNT(image_id) AS nb_images,
        MAX(date_available) AS date_last
-  FROM '.IMAGES_TABLE.'
-    INNER JOIN '.IMAGE_CATEGORY_TABLE.' ON id = image_id
+  FROM '.IMAGES_TABLE.' INNER JOIN '.IMAGE_CATEGORY_TABLE.' ON id = image_id
   WHERE category_id IN ('.wordwrap(implode(', ', $cat_ids), 80, "\n").')
   GROUP BY category_id
 ;';
   $result = pwg_query($query);
   $datas = array();
   $query_ids = array();
-  while ($row = mysql_fetch_array($result))
+  while ( $row = mysql_fetch_array( $result ) )
   {
     array_push($query_ids, $row['category_id']);
 
@@ -466,23 +428,12 @@ SELECT category_id,
   // is returned but the update must be done !
   foreach (array_diff($cat_ids, $query_ids) as $id)
   {
-    array_push(
-      $datas,
-      array(
-        'id'        => $id,
-        'nb_images' => 0,
-        )
-      );
+    array_push($datas, array('id' => $id, 'nb_images' => 0));
   }
 
-  mass_updates(
-    CATEGORIES_TABLE,
-    array(
-      'primary' => array('id'),
-      'update'  => array('date_last', 'nb_images')
-      ),
-    $datas
-    );
+  $fields = array('primary' => array('id'),
+                  'update'  => array('date_last', 'nb_images'));
+  mass_updates(CATEGORIES_TABLE, $fields, $datas);
 
   // representative pictures
   if (count($cat_ids) > 0)
@@ -1357,42 +1308,19 @@ SELECT id, id_uppercat
  */
 function update_path()
 {
-  $images_of = array();
-
   $query = '
-SELECT category_id, image_id
-  FROM '.IMAGE_CATEGORY_TABLE.'
-  WHERE is_storage = \'true\'
+SELECT DISTINCT(storage_category_id)
+  FROM '.IMAGES_TABLE.'
 ;';
-  $result = pwg_query($query);
-  while ($row = mysql_fetch_array($result))
-  {
-    if (!isset($images_of[ $row['category_id'] ]))
-    {
-      $images_of[ $row['category_id'] ] = array();
-    }
+  $cat_ids = array_from_query($query, 'storage_category_id');
+  $fulldirs = get_fulldirs($cat_ids);
 
-    array_push(
-      $images_of[ $row['category_id'] ],
-      $row['image_id']
-      );
-  }
-
-  $fulldirs = get_fulldirs(
-    array_keys($images_of)
-    );
-
-  foreach ($images_of as $cat_id => $image_ids)
+  foreach ($cat_ids as $cat_id)
   {
     $query = '
 UPDATE '.IMAGES_TABLE.'
   SET path = CONCAT(\''.$fulldirs[$cat_id].'\',\'/\',file)
-  WHERE id IN ('.
-      wordwrap(
-        implode(', ', $image_ids),
-        80,
-        "\n").
-      ')
+  WHERE storage_category_id = '.$cat_id.'
 ;';
     pwg_query($query);
   }
@@ -1613,371 +1541,6 @@ DELETE FROM '.$table.'
 }
 
 /**
- * Returns all destinations of a list of source categories. This function
- * solves transitivity.
- *
- * @param mixed array of category ids, empty for all categories
- */
-function get_destinations($categories = 'all')
-{
-  $query = '
-SELECT source, destination
-  FROM '.CATEGORIES_LINK_TABLE.'
-';
-  $result = pwg_query($query);
-
-  $destinations_of = array();
-
-  while ($row = mysql_fetch_array($result))
-  {
-    if (!isset($destinations_of[ $row['source'] ]))
-    {
-      $destinations_of[ $row['source'] ] = array();
-    }
-
-    array_push(
-      $destinations_of[ $row['source'] ],
-      $row['destination']
-      );
-  }
-
-  // transitivity resolution: if " => " means "source of", if A=>B=>C
-  // implies A=>B and A=>C. So A has 2 destinations: B and C.
-  do
-  {
-    // let's suppose we only need a single turn
-    $need_new_turn = false;
-
-    foreach ($destinations_of as $source => $destinations)
-    {
-      foreach ($destinations as $destination)
-      {
-        // does the current destination has destinations itself?
-        if (isset($destinations_of[$destination]))
-        {
-          // are there destinations of current destination not already among
-          // destinations of the current source? (advise: take a piece of
-          // paper and draw a schema). The source itself must not be counted
-          // as a destination, thus avoiding cyclic links.
-          $missing_destinations = array_diff(
-            $destinations_of[$destination],
-            $destinations,
-            array($source) // no cyclic link
-            );
-
-          if (count($missing_destinations) > 0)
-          {
-            $destinations_of[$source] = array_unique(
-              array_merge(
-                $destinations,
-                $missing_destinations
-                )
-              );
-
-            // a category has a least one new destination, we have to check
-            // one more time that it doesn't generate more destinations
-            $need_new_turn = true;
-          }
-        }
-      }
-    }
-  } while ($need_new_turn);
-
-  if (is_array($categories))
-  {
-    $filtered_destinations_of = array();
-
-    // Even if there is no destinations for the requested categories, we
-    // return empty arrays
-    foreach ($categories as $category)
-    {
-      $filtered_destinations_of[$category] = array();
-    }
-
-    foreach ($destinations_of as $source => $destinations)
-    {
-      if (in_array($source, $categories))
-      {
-        $filtered_destinations_of[$source] = $destinations;
-      }
-    }
-
-    return $filtered_destinations_of;
-  }
-  else
-  {
-    return $destinations_of;
-  }
-}
-
-/**
- * Returns all sources of a list of destination categories. This function
- * solves transitivity.
- *
- * @param mixed array of category ids, empty for all categories
- */
-function get_sources($categories = 'all')
-{
-  $destinations_of = get_destinations();
-
-  $sources_of = array();
-
-  foreach ($destinations_of as $source => $destinations)
-  {
-    foreach ($destinations as $destination)
-    {
-      if (!isset($sources_of[$destination]))
-      {
-        $sources_of[$destination] = array();
-      }
-
-      array_push($sources_of[$destination], $source);
-    }
-  }
-
-  // eventually, filter
-  if (is_array($categories))
-  {
-    $filtered_sources_of = array();
-
-    // Even if there is no sources for the requested categories, we return
-    // empty arrays
-    foreach ($categories as $category)
-    {
-      $filtered_sources_of[$category] = array();
-    }
-
-    foreach ($sources_of as $destination => $sources)
-    {
-      if (in_array($destination, $categories))
-      {
-        $filtered_sources_of[$destination] = $sources;
-      }
-    }
-
-    return $filtered_sources_of;
-  }
-  else
-  {
-    return $sources_of;
-  }
-}
-
-/**
- * Checks categories links are respected for a given list of destinations.
- *
- * Checking categories links means that each destination must be associated
- * to the images of its sources.
- *
- * @param mixed source category ids
- */
-function check_links($destinations = 'all')
-{
-  $sources_of = get_sources($destinations);
-
-  if (empty($sources_of))
-  {
-    return true;
-  }
-
-  // we need to search images of all sources and destinations
-  $images_of = array();
-
-  foreach ($sources_of as $destination => $sources)
-  {
-    $images_of[$destination] = array();
-
-    foreach ($sources as $source)
-    {
-      $images_of[$source] = array();
-    }
-  }
-
-  $query = '
-SELECT image_id, category_id
-  FROM '.IMAGE_CATEGORY_TABLE.'
-  WHERE category_id IN ('.
-    implode(',', array_keys($images_of)).
-    ')
-;';
-  $result = pwg_query($query);
-
-  while ($row = mysql_fetch_array($result))
-  {
-    array_push(
-      $images_of[ $row['category_id'] ],
-      $row['image_id']
-      );
-  }
-
-  $inserts = array();
-
-  foreach ($sources_of as $destination => $sources)
-  {
-    // merge all images from the sources of this destination
-    $sources_images = array();
-
-    foreach ($sources as $source)
-    {
-      $sources_images = array_merge(
-        $sources_images,
-        $images_of[$source]
-        );
-    }
-
-    $sources_images = array_unique($sources_images);
-
-    // are there images among the sources that are not linked to the
-    // destination?
-    $missing_images = array_diff(
-      $sources_images,
-      $images_of[$destination]
-      );
-
-    // if we find missing images (missing links in reality), we prepare the
-    // final mass_inserts
-    if (count($missing_images) > 0)
-    {
-      foreach ($missing_images as $missing_image)
-      {
-        array_push(
-          $inserts,
-          array(
-            'category_id' => $destination,
-            'image_id'    => $missing_image,
-            )
-          );
-      }
-    }
-  }
-
-  if (count($inserts) > 0)
-  {
-    mass_inserts(
-      IMAGE_CATEGORY_TABLE,
-      array_keys($inserts[0]),
-      $inserts
-      );
-  }
-}
-
-/**
- * Based on categories links, delete image_category links on destinations.
- *
- * The rule is the following: if an image belong to the category and to the
- * source, we suppose it comes from the source. If the source/destination
- * link is broken, we delete the image/category link if the only origin of
- * the link was the broken categories link.
- *
- * Example: "=>" means "source of". Between brackets the associated images.
- *
- * A (1,2,9) => \
- *               |=> C (1,2,3,4,5,9) => D (1,2,3,4,5,6,9)
- * B (3,4,9) => /
- *
- * In category C, we suppose (1,2) come from A, (3,4) from B, 9 from A or B
- * and 5 was manually added. In category D, 6 was added manually.
- *
- * If we break A=>C, C and D loose (1,2) but not 9 because it can come from
- * B. If we break C=>D, D loose (3,4,5,9) but not 6 because it was
- * associated manually to 9.
- *
- * Warning: only virtual links can be removed, physical links are protected.
- *
- * @param int destination
- * @param array sources
- */
-function delete_sources($destination, $sources)
-{
-  // if no sources to unlink, we stop with OK status
-  if (count($sources) == 0)
-  {
-    return true;
-  }
-
-  $query = '
-DELETE
-  FROM '.CATEGORIES_LINK_TABLE.'
-  WHERE destination = '.$destination.'
-    AND source IN ('.implode(',', $sources).')
-;';
-  pwg_query($query);
-
-  // The strategy is the following:
-  //
-  // * first we brutally delete the image/category associations on
-  // destinations categories for all images belonging to sources.
-  //
-  // * then we check_links on destinations to rebuild missing image/category
-  // associations.
-
-  // what are the images associated to the sources to unlink
-  $query = '
-SELECT image_id
-  FROM '.IMAGE_CATEGORY_TABLE.'
-  WHERE category_id IN ('.
-    implode(',', $sources).
-    ')
-;';
-  $sources_images = array_unique(
-    array_from_query($query, 'image_id')
-    );
-
-  if (count($sources_images) == 0)
-  {
-    return true;
-  }
-
-  // retrieve all direct and indirect destinations of the current
-  // destination
-  $destinations_of = get_destinations(array($destination));
-
-  $destinations = array_merge(
-    array($destination),
-    $destinations_of[$destination]
-    );
-
-  // unlink sources images from destinations
-  $query = '
-DELETE
-  FROM '.IMAGE_CATEGORY_TABLE.'
-  WHERE category_id IN ('.implode(',', $destinations).')
-    AND image_id IN ('.implode(',', $sources_images).')
-    AND is_storage = \'false\'
-;';
-  pwg_query($query);
-
-  // if the representative thumbnail of destinations was a picture from
-  // $sources_images, we request a new random representant
-  $query = '
-SELECT id, representative_picture_id
-  FROM '.CATEGORIES_TABLE.'
-  WHERE id IN ('.implode(',', $destinations).')
-;';
-  $result = pwg_query($query);
-
-  $request_random = array();
-
-  while ($row = mysql_fetch_array($result))
-  {
-    if (isset($row['representative_picture_id']))
-    {
-      if (in_array($row['representative_picture_id'], $sources_images))
-      {
-        array_push($request_random, $row['id']);
-      }
-    }
-  }
-
-  set_random_representant($request_random);
-
-  // eventually, we check_links to rebuild missing associations
-  check_links($destinations);
-
-  return true;
-}
-
-/**
  * create a virtual category
  *
  * @param string category name
@@ -2299,4 +1862,78 @@ function do_maintenance_all_tables()
   pwg_query($query);
 
 }
+
+/**
+ * Associate a list of images to a list of categories.
+ *
+ * The function will not duplicate links
+ *
+ * @param array images
+ * @param array categories
+ * @return void
+ */
+function associate_images_to_categories($images, $categories)
+{
+  if (count($images) == 0
+      or count($categories) == 0)
+  {
+    return false;
+  }
+
+  $query = '
+DELETE
+  FROM '.IMAGE_CATEGORY_TABLE.'
+  WHERE image_id IN ('.implode(',', $images).')
+    AND category_id IN ('.implode(',', $categories).')
+;';
+  pwg_query($query);
+
+  $inserts = array();
+  foreach ($categories as $category_id)
+  {
+    foreach ($images as $image_id)
+    {
+      array_push(
+        $inserts,
+        array(
+          'image_id' => $image_id,
+          'category_id' => $category_id,
+          )
+        );
+    }
+  }
+  
+  mass_inserts(
+    IMAGE_CATEGORY_TABLE,
+    array_keys($inserts[0]),
+    $inserts
+    );
+
+  update_category($categories);
+}
+
+/**
+ * Associate images associated to a list of source categories to a list of
+ * destination categories.
+ *
+ * @param array sources
+ * @param array destinations
+ * @return void
+ */
+function associate_categories_to_categories($sources, $destinations)
+{
+  if (count($sources) == 0)
+  {
+    return false;
+  }
+
+  $query = '
+SELECT image_id
+  FROM '.IMAGE_CATEGORY_TABLE.'
+  WHERE category_id IN ('.implode(',', $sources).')
+;';
+  $images = array_from_query($query, 'image_id');
+
+  associate_images_to_categories($images, $destinations);
+}
 ?>
diff --git a/admin/include/functions_metadata.php b/admin/include/functions_metadata.php
index 21897c2cd..d4324a763 100644
--- a/admin/include/functions_metadata.php
+++ b/admin/include/functions_metadata.php
@@ -246,9 +246,7 @@ SELECT id
   $query = '
 SELECT id, path
   FROM '.IMAGES_TABLE.'
-    INNER JOIN '.IMAGE_CATEGORY_TABLE.' ON image_id = id
-  WHERE is_storage = \'true\'
-    AND category_id IN ('.implode(',', $cat_ids).')';
+  WHERE storage_category_id IN ('.implode(',', $cat_ids).')';
   if ($only_new)
   {
     $query.= '
diff --git a/admin/maintenance.php b/admin/maintenance.php
index de6c2a4a1..2fa60696c 100644
--- a/admin/maintenance.php
+++ b/admin/maintenance.php
@@ -47,7 +47,6 @@ switch ($action)
 {
   case 'categories' :
   {
-    check_links();
     update_uppercats();
     update_category('all');
     ordering();
diff --git a/admin/picture_modify.php b/admin/picture_modify.php
index 83bf09a23..ac7310ddd 100644
--- a/admin/picture_modify.php
+++ b/admin/picture_modify.php
@@ -121,56 +121,23 @@ if (isset($_POST['associate'])
     and isset($_POST['cat_dissociated'])
     and count($_POST['cat_dissociated']) > 0)
 {
-  $datas = array();
-
-  foreach ($_POST['cat_dissociated'] as $category_id)
-  {
-    array_push(
-      $datas,
-      array(
-        'image_id' => $_GET['image_id'],
-        'category_id' => $category_id
-        )
-      );
-  }
-
-  mass_inserts(
-    IMAGE_CATEGORY_TABLE,
-    array('image_id', 'category_id'),
-    $datas
+  associate_images_to_categories(
+    array($_GET['image_id']),
+    $_POST['cat_dissociated']
     );
-
-  check_links();
-  update_category($_POST['cat_dissociated']);
 }
 // dissociate the element from categories (but not from its storage category)
 if (isset($_POST['dissociate'])
     and isset($_POST['cat_associated'])
     and count($_POST['cat_associated']) > 0)
 {
-  $associated_categories = $_POST['cat_associated'];
-
-  // If the same element is associated to a source and its destinations,
-  // dissociating the element with the source implies dissociating the
-  // element fwith the destination.
-  $destinations_of = get_destinations($_POST['cat_associated']);
-  foreach ($destinations_of as $source => $destinations)
-  {
-    $associated_categories = array_merge(
-      $associated_categories,
-      $destinations
-      );
-  }
-
   $query = '
 DELETE FROM '.IMAGE_CATEGORY_TABLE.'
   WHERE image_id = '.$_GET['image_id'].'
-    AND category_id IN ('.implode(',', $associated_categories).')
-    AND is_storage = \'false\'
+    AND category_id IN ('.implode(',', $_POST['cat_associated']).')
 ';
   pwg_query($query);
-
-  check_links();
+  
   update_category($_POST['cat_associated']);
 }
 // elect the element to represent the given categories
@@ -201,13 +168,11 @@ if (isset($_POST['dismiss'])
 $query = '
 SELECT *
   FROM '.IMAGES_TABLE.'
-    INNER JOIN '.IMAGE_CATEGORY_TABLE.' ON image_id = id
   WHERE id = '.$_GET['image_id'].'
-    AND is_storage = \'true\'
 ;';
 $row = mysql_fetch_array(pwg_query($query));
 
-$storage_category_id = $row['category_id'];
+$storage_category_id = $row['storage_category_id'];
 $image_file = $row['file'];
 
 // tags
@@ -396,7 +361,7 @@ SELECT id,name,uppercats,global_rank
   FROM '.CATEGORIES_TABLE.'
     INNER JOIN '.IMAGE_CATEGORY_TABLE.' ON id = category_id
   WHERE image_id = '.$_GET['image_id'].'
-    AND is_storage = \'false\'
+    AND id != '.$storage_category_id.'
 ;';
 display_select_cat_wrapper($query, array(), 'associated_option');
 
diff --git a/admin/rating.php b/admin/rating.php
index 76b4aa865..86f95205a 100644
--- a/admin/rating.php
+++ b/admin/rating.php
@@ -182,16 +182,14 @@ SELECT i.id,
        i.file,
        i.tn_ext,
        i.average_rate,
+       i.storage_category_id,
        MAX(r.date)          AS recently_rated,
        COUNT(r.rate)        AS nb_rates,
        SUM(r.rate)          AS sum_rates,
-       ROUND(STD(r.rate),2) AS std_rates,
-       ic.category_id       AS storage_category_id
+       ROUND(STD(r.rate),2) AS std_rates
   FROM '.RATE_TABLE.' AS r
     LEFT JOIN '.IMAGES_TABLE.' AS i ON r.element_id = i.id
-    INNER JOIN '.IMAGE_CATEGORY_TABLE.' AS ic ON ic.image_id = i.id
   WHERE 1 = 1 ' . $display_filter . '
-    AND ic.is_storage = \'true\'
   GROUP BY r.element_id
   ORDER BY ' . $available_order_by[$order_by_index][1] .'
   LIMIT '.$start.','.$elements_per_page.'
diff --git a/admin/site_update.php b/admin/site_update.php
index c7c31106c..3562046ae 100644
--- a/admin/site_update.php
+++ b/admin/site_update.php
@@ -368,15 +368,12 @@ if (isset($_POST['submit']) and $_POST['sync'] == 'files'
     $query = '
 SELECT id, path
   FROM '.IMAGES_TABLE.'
-    INNER JOIN '.IMAGE_CATEGORY_TABLE.' ON image_id = id
-  WHERE is_storage = \'true\'
-    AND category_id IN ('.
-      wordwrap(
+  WHERE storage_category_id IN ('
+      .wordwrap(
         implode(', ', $cat_ids),
         80,
         "\n"
-        ).
-      ')
+        ).')
 ;';
     $result = pwg_query($query);
     while ($row = mysql_fetch_array($result))
@@ -458,6 +455,7 @@ SELECT IF(MAX(id)+1 IS NULL, 1, MAX(id)+1) AS next_element_id
             ? $fs[$path]['has_high']
             : null,
           'path'           => $path,
+          'storage_category_id' => $db_fulldirs[$dirname],
           );
 
         array_push(
@@ -469,8 +467,7 @@ SELECT IF(MAX(id)+1 IS NULL, 1, MAX(id)+1) AS next_element_id
           $insert_links,
           array(
             'image_id'    => $insert{'id'},
-            'category_id' => $db_fulldirs[$dirname],
-            'is_storage'  => 'true',
+            'category_id' => $insert['storage_category_id'],
             )
           );
         array_push(
@@ -508,6 +505,7 @@ SELECT IF(MAX(id)+1 IS NULL, 1, MAX(id)+1) AS next_element_id
         'representative_ext' => isset($fs[$path]['representative_ext'])
           ? $fs[$path]['representative_ext']
           : null,
+        'storage_category_id' => $db_fulldirs[$dirname],
         );
 
       array_push(
@@ -519,8 +517,7 @@ SELECT IF(MAX(id)+1 IS NULL, 1, MAX(id)+1) AS next_element_id
         $insert_links,
         array(
           'image_id'    => $insert{'id'},
-          'category_id' => $db_fulldirs[$dirname],
-          'is_storage'  => 'true',
+          'category_id' => $insert['storage_category_id'],
           )
         );
 
@@ -552,7 +549,7 @@ SELECT IF(MAX(id)+1 IS NULL, 1, MAX(id)+1) AS next_element_id
       mass_inserts(
         IMAGE_CATEGORY_TABLE,
         array(
-          'image_id','category_id', 'is_storage',
+          'image_id','category_id',
           ),
         $insert_links
         );
@@ -609,9 +606,7 @@ SELECT id,file,storage_category_id,infos
       $query = '
 SELECT id
   FROM '.IMAGES_TABLE.'
-    INNER JOIN '.IMAGE_CATEGORY_TABLE.' ON image_id = id
-  WHERE is_storage = \'true\'
-    AND category_id = '.$row['storage_category_id'].'
+  WHERE storage_category_id = '.$row['storage_category_id'].'
     AND file = \''.$row['file'].'\'
 ;';
       list($data['id']) = mysql_fetch_array(pwg_query($query));
@@ -659,11 +654,6 @@ if (isset($_POST['submit'])
   if (!$simulate)
   {
     $start = get_moment();
-    check_links('all');
-    echo '<!-- check_links(all) : ';
-    echo get_elapsed_time($start,get_moment());
-    echo ' -->'."\n";
-    $start = get_moment();
     update_category('all');
     echo '<!-- update_category(all) : ';
     echo get_elapsed_time($start,get_moment());