diff --git a/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/KeyValue/FieldKey.php b/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/KeyValue/FieldKey.php
index f4f8553738..293e8c69dd 100644
--- a/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/KeyValue/FieldKey.php
+++ b/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/KeyValue/FieldKey.php
@@ -30,6 +30,11 @@ class FieldKey implements Key, QueryPostProcessor
         return $this->getField($context)->getIndexField($raw);
     }
 
+    public function getFieldType(QueryContext $context)
+    {
+        return $this->getField($context)->getType();
+    }
+
     public function isValueCompatible($value, QueryContext $context)
     {
         return ValueChecker::isValueCompatible($this->getField($context), $value);
diff --git a/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/KeyValue/Key.php b/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/KeyValue/Key.php
index 20ee045a59..d664fccb94 100644
--- a/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/KeyValue/Key.php
+++ b/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/KeyValue/Key.php
@@ -6,6 +6,7 @@ use Alchemy\Phrasea\SearchEngine\Elastic\Search\QueryContext;
 
 interface Key
 {
+    public function getFieldType(QueryContext $context);
     public function getIndexField(QueryContext $context, $raw = false);
     public function isValueCompatible($value, QueryContext $context);
     public function __toString();
diff --git a/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/KeyValue/MetadataKey.php b/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/KeyValue/MetadataKey.php
index 292b6e7237..61f9303fe0 100644
--- a/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/KeyValue/MetadataKey.php
+++ b/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/KeyValue/MetadataKey.php
@@ -23,6 +23,11 @@ class MetadataKey implements Key
         return $this->getTag($context)->getIndexField($raw);
     }
 
+    public function getFieldType(QueryContext $context)
+    {
+        return $this->getTag($context)->getType();
+    }
+
     public function isValueCompatible($value, QueryContext $context)
     {
         return ValueChecker::isValueCompatible($this->getTag($context), $value);
diff --git a/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/KeyValue/NativeKey.php b/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/KeyValue/NativeKey.php
index e486483b71..3c2d334f48 100644
--- a/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/KeyValue/NativeKey.php
+++ b/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/KeyValue/NativeKey.php
@@ -52,6 +52,11 @@ class NativeKey implements Key
         $this->key = $key;
     }
 
+    public function getFieldType(QueryContext $context)
+    {
+        return $this->type;
+    }
+
     public function getIndexField(QueryContext $context, $raw = false)
     {
         return $this->key;
diff --git a/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/KeyValue/RangeExpression.php b/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/KeyValue/RangeExpression.php
index ec785354ae..17f901a77c 100644
--- a/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/KeyValue/RangeExpression.php
+++ b/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/KeyValue/RangeExpression.php
@@ -2,18 +2,20 @@
 
 namespace Alchemy\Phrasea\SearchEngine\Elastic\AST\KeyValue;
 
+use Alchemy\Phrasea\SearchEngine\Elastic\FieldMapping;
+use Alchemy\Phrasea\SearchEngine\Elastic\RecordHelper;
+use Alchemy\Phrasea\SearchEngine\Elastic\Structure\Field as StructureField;
 use Assert\Assertion;
-use Alchemy\Phrasea\SearchEngine\Elastic\AST\KeyValue\FieldKey;
-use Alchemy\Phrasea\SearchEngine\Elastic\AST\KeyValue\Key;
 use Alchemy\Phrasea\SearchEngine\Elastic\AST\Node;
 use Alchemy\Phrasea\SearchEngine\Elastic\Exception\QueryException;
 use Alchemy\Phrasea\SearchEngine\Elastic\Search\QueryContext;
-use Alchemy\Phrasea\SearchEngine\Elastic\Search\QueryHelper;
 use Alchemy\Phrasea\SearchEngine\Elastic\Search\QueryPostProcessor;
 
 class RangeExpression extends Node
 {
+    /** @var FieldKey  */
     private $key;
+
     private $lower_bound;
     private $lower_inclusive;
     private $higher_bound;
@@ -55,20 +57,34 @@ class RangeExpression extends Node
     public function buildQuery(QueryContext $context)
     {
         $params = array();
-        if ($this->lower_bound !== null) {
-            $this->assertValueCompatible($this->lower_bound, $context);
-            if ($this->lower_inclusive) {
-                $params['gte'] = $this->lower_bound;
-            } else {
-                $params['gt'] = $this->lower_bound;
+        /** @var StructureField $field */
+        // $field = $this->key->getField($context);
+        $lower_bound = $this->lower_bound;
+        $higher_bound = $this->higher_bound;
+
+        if($this->key->getFieldType($context) === FieldMapping::TYPE_DATE) {
+            if($lower_bound !== null) {
+                $lower_bound = RecordHelper::sanitizeDate($lower_bound);
+            }
+            if($higher_bound !== null) {
+                $higher_bound = RecordHelper::sanitizeDate($higher_bound);
             }
         }
-        if ($this->higher_bound !== null) {
-            $this->assertValueCompatible($this->higher_bound, $context);
-            if ($this->higher_inclusive) {
-                $params['lte'] = $this->higher_bound;
+
+        if ($lower_bound !== null) {
+            $this->assertValueCompatible($lower_bound, $context);
+            if ($this->lower_inclusive) {
+                $params['gte'] = $lower_bound;
             } else {
-                $params['lt'] = $this->higher_bound;
+                $params['gt'] = $lower_bound;
+            }
+        }
+        if ($higher_bound !== null) {
+            $this->assertValueCompatible($higher_bound, $context);
+            if ($this->higher_inclusive) {
+                $params['lte'] = $higher_bound;
+            } else {
+                $params['lt'] = $higher_bound;
             }
         }
 
diff --git a/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/KeyValue/TimestampKey.php b/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/KeyValue/TimestampKey.php
index b879945982..a5d34909d7 100644
--- a/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/KeyValue/TimestampKey.php
+++ b/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/KeyValue/TimestampKey.php
@@ -34,6 +34,11 @@ class TimestampKey implements Key, Typed
         return FieldMapping::TYPE_DATE;
     }
 
+    public function getFieldType(QueryContext $context)
+    {
+        return FieldMapping::TYPE_DATE;
+    }
+
     public function getIndexField(QueryContext $context, $raw = false)
     {
         return $this->index_field;
diff --git a/lib/Alchemy/Phrasea/SearchEngine/Elastic/ElasticSearchEngine.php b/lib/Alchemy/Phrasea/SearchEngine/Elastic/ElasticSearchEngine.php
index ed9d3ceeed..63d9ec108e 100644
--- a/lib/Alchemy/Phrasea/SearchEngine/Elastic/ElasticSearchEngine.php
+++ b/lib/Alchemy/Phrasea/SearchEngine/Elastic/ElasticSearchEngine.php
@@ -396,10 +396,10 @@ class ElasticSearchEngine implements SearchEngineInterface
         if ($options->getDateFields() && ($options->getMaxDate() || $options->getMinDate())) {
             $range = [];
             if ($options->getMaxDate()) {
-                $range['lte'] = $options->getMaxDate()->format(FieldMapping::DATE_FORMAT_CAPTION_PHP);
+                $range['lte'] = $options->getMaxDate()->format('Y-m-d');
             }
             if ($options->getMinDate()) {
-                $range['gte'] = $options->getMinDate()->format(FieldMapping::DATE_FORMAT_CAPTION_PHP);
+                $range['gte'] = $options->getMinDate()->format('Y-m-d');
             }
 
             foreach ($options->getDateFields() as $dateField) {
diff --git a/lib/Alchemy/Phrasea/SearchEngine/Elastic/FieldMapping.php b/lib/Alchemy/Phrasea/SearchEngine/Elastic/FieldMapping.php
index 076034b7b1..7a60b066e6 100644
--- a/lib/Alchemy/Phrasea/SearchEngine/Elastic/FieldMapping.php
+++ b/lib/Alchemy/Phrasea/SearchEngine/Elastic/FieldMapping.php
@@ -16,8 +16,7 @@ class FieldMapping
 
     const DATE_FORMAT_MYSQL = 'yyyy-MM-dd HH:mm:ss';
     const DATE_FORMAT_CAPTION = 'yyyy/MM/dd'; // ES format
-    const DATE_FORMAT_MYSQL_OR_CAPTION = 'yyyy-MM-dd HH:mm:ss||yyyy/MM/dd';
-    const DATE_FORMAT_CAPTION_PHP = 'Y/m/d';  // PHP format
+    const DATE_FORMAT_MYSQL_OR_CAPTION = 'yyyy-MM-dd HH:mm:ss||yyyy-MM-dd||yyyy-MM||yyyy';
 
     // Core types
     const TYPE_STRING     = 'string';
diff --git a/lib/Alchemy/Phrasea/SearchEngine/Elastic/Mapping/DateFieldMapping.php b/lib/Alchemy/Phrasea/SearchEngine/Elastic/Mapping/DateFieldMapping.php
index a96ef45f4a..128a16467f 100644
--- a/lib/Alchemy/Phrasea/SearchEngine/Elastic/Mapping/DateFieldMapping.php
+++ b/lib/Alchemy/Phrasea/SearchEngine/Elastic/Mapping/DateFieldMapping.php
@@ -57,6 +57,9 @@ class DateFieldMapping extends ComplexFieldMapping
      */
     protected function getProperties()
     {
-        return array_merge([ 'format' => $this->format ], parent::getProperties());
+        return array_merge([
+            'format' => $this->format,
+            'ignore_malformed' => true
+            ], parent::getProperties());
     }
 }
diff --git a/lib/Alchemy/Phrasea/SearchEngine/Elastic/RecordHelper.php b/lib/Alchemy/Phrasea/SearchEngine/Elastic/RecordHelper.php
index ffb0c71adf..83ca222593 100644
--- a/lib/Alchemy/Phrasea/SearchEngine/Elastic/RecordHelper.php
+++ b/lib/Alchemy/Phrasea/SearchEngine/Elastic/RecordHelper.php
@@ -89,31 +89,45 @@ class RecordHelper
         return $this->collectionMap;
     }
 
-    /**
-     * @param string $date
-     * @return bool
-     */
-    public static function validateDate($date)
-    {
-        $d = DateTime::createFromFormat(FieldMapping::DATE_FORMAT_CAPTION_PHP, $date);
-
-        return $d && $d->format(FieldMapping::DATE_FORMAT_CAPTION_PHP) == $date;
-    }
-
     /**
      * @param string $value
      * @return null|string
      */
     public static function sanitizeDate($value)
     {
-        // introduced in https://github.com/alchemy-fr/Phraseanet/commit/775ce804e0257d3a06e4e068bd17330a79eb8370#diff-bee690ed259e0cf73a31dee5295d2edcR286
-        // not sure if it's really needed
+        $v_fix = null;
         try {
-            $date = new \DateTime($value);
-
-            return $date->format(FieldMapping::DATE_FORMAT_CAPTION_PHP);
+            $a = explode(';', preg_replace('/\D+/', ';', trim($value)));
+            switch (count($a)) {
+                case 1:     // yyyy
+                    $date = new \DateTime($a[0] . '-01-01');    // will throw if date is not valid
+                    $v_fix = $date->format('Y');
+                    break;
+                case 2:     // yyyy;mm
+                    $date = new \DateTime( $a[0] . '-' . $a[1] . '-01');
+                    $v_fix = $date->format('Y-m');
+                    break;
+                case 3:     // yyyy;mm;dd
+                    $date = new \DateTime($a[0] . '-' . $a[1] . '-' . $a[2]);
+                    $v_fix = $date->format('Y-m-d');
+                    break;
+                case 4:
+                    $date = new \DateTime($a[0] . '-' . $a[1] . '-' . $a[2] . ' ' . $a[3] . ':00:00');
+                    $v_fix = $date->format('Y-m-d H:i:s');
+                    break;
+                case 5:
+                    $date = new \DateTime($a[0] . '-' . $a[1] . '-' . $a[2] . ' ' . $a[3] . ':' . $a[4] . ':00');
+                    $v_fix = $date->format('Y-m-d H:i:s');
+                    break;
+                case 6:
+                    $date = new \DateTime($a[0] . '-' . $a[1] . '-' . $a[2] . ' ' . $a[3] . ':' . $a[4] . ':' . $a[5]);
+                    $v_fix = $date->format('Y-m-d H:i:s');
+                    break;
+            }
         } catch (\Exception $e) {
-            return null;
+            // no-op, v_fix = null
         }
+
+        return $v_fix;
     }
 }
diff --git a/lib/Alchemy/Phrasea/SearchEngine/Elastic/Search/QueryHelper.php b/lib/Alchemy/Phrasea/SearchEngine/Elastic/Search/QueryHelper.php
index 1acdd5935c..071ac94b1c 100644
--- a/lib/Alchemy/Phrasea/SearchEngine/Elastic/Search/QueryHelper.php
+++ b/lib/Alchemy/Phrasea/SearchEngine/Elastic/Search/QueryHelper.php
@@ -110,41 +110,50 @@ class QueryHelper
         }
     }
 
-    public static function getRangeFromDateString($string)
+    public static function getRangeFromDateString($value)
     {
-        $formats = ['Y/m/d', 'Y/m', 'Y'];
-        $deltas = ['+1 day', '+1 month', '+1 year'];
-        $to = null;
-        while ($format = array_pop($formats)) {
-            $delta = array_pop($deltas);
-            $from = date_create_from_format($format, $string);
-            if ($from !== false) {
-                // Rewind to start of range
-                $month = 1;
-                $day = 1;
-                switch ($format) {
-                    case 'Y/m/d':
-                        $day = (int) $from->format('d');
-                    case 'Y/m':
-                        $month = (int) $from->format('m');
-                    case 'Y':
-                        $year = (int) $from->format('Y');
-                }
-                date_date_set($from, $year, $month, $day);
-                date_time_set($from, 0, 0, 0);
-                // Create end of the the range
-                $to = date_modify(clone $from, $delta);
-                break;
+        $date_from = null;
+        $date_to   = null;
+        try {
+            $a = explode(';', preg_replace('/\D+/', ';', trim($value)));
+            switch (count($a)) {
+                case 1:     // yyyy
+                    $date_to = clone($date_from = new \DateTime($a[0] . '-01-01 00:00:00'));    // will throw if date is not valid
+                    $date_to->add(new \DateInterval('P1Y'));
+                    break;
+                case 2:     // yyyy;mm
+                    $date_to = clone($date_from = new \DateTime($a[0] . '-' . $a[1] . '-01 00:00:00'));    // will throw if date is not valid
+                    $date_to->add(new \DateInterval('P1M'));
+                    break;
+                case 3:     // yyyy;mm;dd
+                    $date_to = clone($date_from = new \DateTime($a[0] . '-' . $a[1] . '-' . $a[2] . ' 00:00:00'));    // will throw if date is not valid
+                    $date_to->add(new \DateInterval('P1D'));
+                    break;
+                case 4:
+                    $date_to = clone($date_from = new \DateTime($a[0] . '-' . $a[1] . '-' . $a[2] . ' ' . $a[3] . ':00:00'));
+                    $date_to->add(new \DateInterval('PT1H'));
+                    break;
+                case 5:
+                    $date_to = clone($date_from = new \DateTime($a[0] . '-' . $a[1] . '-' . $a[2] . ' ' . $a[3] . ':' . $a[4] . ':00'));
+                    $date_to->add(new \DateInterval('PT1M'));
+                    break;
+                case 6:
+                    $date_to = clone($date_from = new \DateTime($a[0] . '-' . $a[1] . '-' . $a[2] . ' ' . $a[3] . ':' . $a[4] . ':' . $a[5]));
+                    // $date_to->add(new \DateInterval('PT1S'));    // no need since precision is 1 sec, a "equal" will be generated when from==to
+                    break;
             }
         }
+        catch (\Exception $e) {
+            // no-op
+        }
 
-        if (!$from || !$to) {
-            throw new \InvalidArgumentException(sprintf('Invalid date "%s".', $string));
+        if ($date_from === null || $date_to === null) {
+            throw new \InvalidArgumentException(sprintf('Invalid date "%s".', $value));
         }
 
         return [
-            'from' => $from->format(FieldMapping::DATE_FORMAT_CAPTION_PHP),
-            'to'   => $to->format(FieldMapping::DATE_FORMAT_CAPTION_PHP)
+            'from' => $date_from->format('Y-m-d H:i:s'),
+            'to'   => $date_to->format('Y-m-d H:i:s')
         ];
     }
 }
diff --git a/lib/Alchemy/Phrasea/SearchEngine/Elastic/Search/QueryVisitor.php b/lib/Alchemy/Phrasea/SearchEngine/Elastic/Search/QueryVisitor.php
index 522666bcaa..52c0fa54a6 100644
--- a/lib/Alchemy/Phrasea/SearchEngine/Elastic/Search/QueryVisitor.php
+++ b/lib/Alchemy/Phrasea/SearchEngine/Elastic/Search/QueryVisitor.php
@@ -5,7 +5,7 @@ namespace Alchemy\Phrasea\SearchEngine\Elastic\Search;
 use Alchemy\Phrasea\SearchEngine\Elastic\AST;
 use Alchemy\Phrasea\SearchEngine\Elastic\Exception\Exception;
 use Alchemy\Phrasea\SearchEngine\Elastic\FieldMapping;
-use Alchemy\Phrasea\SearchEngine\Elastic\Mapping;
+use Alchemy\Phrasea\SearchEngine\Elastic\RecordHelper;
 use Alchemy\Phrasea\SearchEngine\Elastic\Structure\Structure;
 use Hoa\Compiler\Llk\TreeNode;
 use Hoa\Visitor\Element;
@@ -166,6 +166,12 @@ class QueryVisitor implements Visit
         $key = $node->getChild(0)->accept($this);
         $boundary = $node->getChild(1)->accept($this);
 
+        if ($this->isDateKey($key)) {
+            if(($v = RecordHelper::sanitizeDate($boundary)) !== null) {
+                $boundary = $v;
+            }
+        }
+
         switch ($node->getId()) {
             case NodeTypes::LT_EXPR:
                 return AST\KeyValue\RangeExpression::lessThan($key, $boundary);
@@ -195,11 +201,15 @@ class QueryVisitor implements Visit
                 try {
                     // Try to create a range for incomplete dates
                     $range = QueryHelper::getRangeFromDateString($right);
-                    return new AST\KeyValue\RangeExpression(
-                        $left,
-                        $range['from'], true,
-                        $range['to'], false
-                    );
+                    if ($range['from'] === $range['to']) {
+                        return new AST\KeyValue\EqualExpression($left, $range['from']);
+                    } else {
+                        return new AST\KeyValue\RangeExpression(
+                            $left,
+                            $range['from'], true,
+                            $range['to'], false
+                        );
+                    }
                 } catch (\InvalidArgumentException $e) {
                     // Fall back to equal expression
                 }
diff --git a/lib/Alchemy/Phrasea/SearchEngine/Elastic/Structure/ValueChecker.php b/lib/Alchemy/Phrasea/SearchEngine/Elastic/Structure/ValueChecker.php
index 31f65c580e..f27defa2bb 100644
--- a/lib/Alchemy/Phrasea/SearchEngine/Elastic/Structure/ValueChecker.php
+++ b/lib/Alchemy/Phrasea/SearchEngine/Elastic/Structure/ValueChecker.php
@@ -3,7 +3,6 @@
 namespace Alchemy\Phrasea\SearchEngine\Elastic\Structure;
 
 use Alchemy\Phrasea\SearchEngine\Elastic\FieldMapping;
-use Alchemy\Phrasea\SearchEngine\Elastic\Mapping;
 use Alchemy\Phrasea\SearchEngine\Elastic\RecordHelper;
 use Assert\Assertion;
 
@@ -20,7 +19,7 @@ class ValueChecker
     {
         Assertion::allIsInstanceOf($list, Typed::class);
         $is_numeric = is_numeric($value);
-        $is_valid_date = RecordHelper::validateDate($value);
+        $is_valid_date = (RecordHelper::sanitizeDate($value) !== null);
         $filtered = [];
         foreach ($list as $item) {
             switch ($item->getType()) {
diff --git a/lib/Alchemy/Phrasea/TaskManager/Job/WriteMetadataJob.php b/lib/Alchemy/Phrasea/TaskManager/Job/WriteMetadataJob.php
index f35b8e806e..795b0b2a83 100644
--- a/lib/Alchemy/Phrasea/TaskManager/Job/WriteMetadataJob.php
+++ b/lib/Alchemy/Phrasea/TaskManager/Job/WriteMetadataJob.php
@@ -127,7 +127,10 @@ class WriteMetadataJob extends AbstractJob
 
                     // check exiftool known tags to skip Phraseanet:tf-*
                     try {
-                        TagFactory::getFromRDFTagname($tagName);
+                        $tag = TagFactory::getFromRDFTagname($tagName);
+                        if(!$tag->isWritable()) {
+                            continue;
+                        }
                     } catch (TagUnknown $e) {
                         continue;
                     }
@@ -147,21 +150,34 @@ class WriteMetadataJob extends AbstractJob
                             $fieldValue = array_pop($fieldValues);
                             $value = $this->removeNulChar($fieldValue->getValue());
 
-                            $value = new Value\Mono($value);
+                            // fix the dates edited into phraseanet
+                            if($fieldStructure->get_type() === $fieldStructure::TYPE_DATE) {
+                                try {
+                                    $value = self::fixDate($value); // will return NULL if the date is not valid
+                                }
+                                catch (\Exception $e) {
+                                    $value = null;    // do NOT write back to iptc
+                                }
+                            }
+
+                            if($value !== null) {   // do not write invalid dates
+                                $value = new Value\Mono($value);
+                            }
                         }
-                    } catch(\Exception $e) {
+                    } catch (\Exception $e) {
                         // the field is not set in the record, erase it
                         if ($fieldStructure->is_multi()) {
                             $value = new Value\Multi(array(''));
-                        }
-                        else {
+                        } else {
                             $value = new Value\Mono('');
                         }
                     }
 
-                    $metadata->add(
-                        new Metadata\Metadata($fieldStructure->get_tag(), $value)
-                    );
+                    if($value !== null) {   // do not write invalid data
+                        $metadata->add(
+                            new Metadata\Metadata($fieldStructure->get_tag(), $value)
+                        );
+                    }
                 }
 
                 $writer = $this->getMetadataWriter($jobData->getApplication());
@@ -220,4 +236,34 @@ class WriteMetadataJob extends AbstractJob
     {
         return str_replace("\0", "", $value);
     }
+
+    /**
+     * re-format a phraseanet date for iptc writing
+     * return NULL if the date is not valid
+     *
+     * @param string $value
+     * @return string|null
+     */
+    private static function fixDate($value)
+    {
+        $date = null;
+        try {
+            $a = explode(';', preg_replace('/\D+/', ';', trim($value)));
+            switch (count($a)) {
+                case 3:     // yyyy;mm;dd
+                    $date = new \DateTime($a[0] . '-' . $a[1] . '-' . $a[2]);
+                    $date = $date->format('Y-m-d H:i:s');
+                    break;
+                case 6:     // yyyy;mm;dd;hh;mm;ss
+                    $date = new \DateTime($a[0] . '-' . $a[1] . '-' . $a[2] . ' ' . $a[3] . ':' . $a[4] . ':' . $a[5]);
+                    $date = $date->format('Y-m-d H:i:s');
+                    break;
+            }
+        }
+        catch (\Exception $e) {
+            $date = null;
+        }
+
+        return $date;
+    }
 }
diff --git a/tests/Alchemy/Tests/Phrasea/SearchEngine/AST/RangeExpressionTest.php b/tests/Alchemy/Tests/Phrasea/SearchEngine/AST/RangeExpressionTest.php
index 88a850fe03..d1d376e37b 100644
--- a/tests/Alchemy/Tests/Phrasea/SearchEngine/AST/RangeExpressionTest.php
+++ b/tests/Alchemy/Tests/Phrasea/SearchEngine/AST/RangeExpressionTest.php
@@ -58,6 +58,7 @@ class RangeExpressionTest extends \PHPUnit_Framework_TestCase
     {
         $query_context = $this->prophesize(QueryContext::class)->reveal();
         $key_prophecy = $this->prophesize(Key::class);
+        $key_prophecy->getFieldType($query_context)->willReturn('text');
         $key_prophecy->getIndexField($query_context)->willReturn('foo');
         $key_prophecy->isValueCompatible('bar', $query_context)->willReturn(true);
         $key = $key_prophecy->reveal();
@@ -73,6 +74,7 @@ class RangeExpressionTest extends \PHPUnit_Framework_TestCase
     {
         $query_context = $this->prophesize(QueryContext::class)->reveal();
         $key = $this->prophesize(FieldKey::class);
+        $key->getFieldType($query_context)->willReturn('text');
         $key->getIndexField($query_context)->willReturn('baz');
         $key->isValueCompatible('bar', $query_context)->willReturn(true);
         $key->postProcessQuery(Argument::any(), $query_context)->willReturnArgument(0);
diff --git a/tests/Alchemy/Tests/Phrasea/SearchEngine/resources/queries.csv b/tests/Alchemy/Tests/Phrasea/SearchEngine/resources/queries.csv
index 9f7d079880..5252788eaa 100644
--- a/tests/Alchemy/Tests/Phrasea/SearchEngine/resources/queries.csv
+++ b/tests/Alchemy/Tests/Phrasea/SearchEngine/resources/queries.csv
@@ -53,6 +53,7 @@ foo < 42|<range:field.foo lt="42">
 foo ≤ 42|<range:field.foo lte="42">
 foo > 42|<range:field.foo gt="42">
 foo ≥ 42|<range:field.foo gte="42">
+foo = 2015/01/01|(<field.foo> == <value:"2015/01/01">)
 foo < 2015/01/01|<range:field.foo lt="2015/01/01">
 foo ≤ 2015/01/01|<range:field.foo lte="2015/01/01">
 foo > 2015/01/01|<range:field.foo gt="2015/01/01">
@@ -93,19 +94,93 @@ id:90 AND foo|(<record_identifier:"90"> AND <text:"foo">)
 id:90 foo|(<record_identifier:"90"> AND <text:"foo">)
 recordid:90|<record_identifier:"90">
 
-# Timestamps
-created_on < "2015/01/01"|<range:creation lt="2015/01/01">
-created_on ≤ "2015/01/01"|<range:creation lte="2015/01/01">
-created_on = "2015/01/01"|<range:creation gte="2015/01/01" lt="2015/01/02">
-created_on ≥ "2015/01/01"|<range:creation gte="2015/01/01">
-created_on > "2015/01/01"|<range:creation gt="2015/01/01">
-updated_on < "2015/01/01"|<range:update lt="2015/01/01">
-updated_on ≤ "2015/01/01"|<range:update lte="2015/01/01">
-updated_on = "2015/01/01"|<range:update gte="2015/01/01" lt="2015/01/02">
-updated_on ≥ "2015/01/01"|<range:update gte="2015/01/01">
-updated_on > "2015/01/01"|<range:update gt="2015/01/01">
-created_at > "2015/01/01"|<range:creation gt="2015/01/01">
-updated_at > "2015/01/01"|<range:update gt="2015/01/01">
+# Timestamps yyyy
+created_on < "2015"|<range:creation lt="2015">
+created_on ≤ "2015"|<range:creation lte="2015">
+created_on = "2015"|<range:creation gte="2015-01-01 00:00:00" lt="2016-01-01 00:00:00">
+created_on ≥ "2015"|<range:creation gte="2015">
+created_on > "2015"|<range:creation gt="2015">
+updated_on < "2015"|<range:update lt="2015">
+updated_on ≤ "2015"|<range:update lte="2015">
+updated_on = "2015"|<range:update gte="2015-01-01 00:00:00" lt="2016-01-01 00:00:00">
+updated_on ≥ "2015"|<range:update gte="2015">
+updated_on > "2015"|<range:update gt="2015">
+created_at > "2015"|<range:creation gt="2015">
+updated_at > "2015"|<range:update gt="2015">
+
+# Timestamps yyyy/mm
+created_on < "2015/01"|<range:creation lt="2015-01">
+created_on ≤ "2015/01"|<range:creation lte="2015-01">
+created_on = "2015/01"|<range:creation gte="2015-01-01 00:00:00" lt="2015-02-01 00:00:00">
+created_on ≥ "2015/01"|<range:creation gte="2015-01">
+created_on > "2015/01"|<range:creation gt="2015-01">
+updated_on < "2015/01"|<range:update lt="2015-01">
+updated_on ≤ "2015/01"|<range:update lte="2015-01">
+updated_on = "2015/01"|<range:update gte="2015-01-01 00:00:00" lt="2015-02-01 00:00:00">
+updated_on ≥ "2015/01"|<range:update gte="2015-01">
+updated_on > "2015/01"|<range:update gt="2015-01">
+created_at > "2015/01"|<range:creation gt="2015-01">
+updated_at > "2015/01"|<range:update gt="2015-01">
+
+# Timestamps yyyy/mm/dd
+created_on < "2015/01/01"|<range:creation lt="2015-01-01">
+created_on ≤ "2015/01/01"|<range:creation lte="2015-01-01">
+created_on = "2015/01/01"|<range:creation gte="2015-01-01 00:00:00" lt="2015-01-02 00:00:00">
+created_on ≥ "2015/01/01"|<range:creation gte="2015-01-01">
+created_on > "2015/01/01"|<range:creation gt="2015-01-01">
+updated_on < "2015/01/01"|<range:update lt="2015-01-01">
+updated_on ≤ "2015/01/01"|<range:update lte="2015-01-01">
+updated_on = "2015/01/01"|<range:update gte="2015-01-01 00:00:00" lt="2015-01-02 00:00:00">
+updated_on ≥ "2015/01/01"|<range:update gte="2015-01-01">
+updated_on > "2015/01/01"|<range:update gt="2015-01-01">
+created_at > "2015/01/01"|<range:creation gt="2015-01-01">
+updated_at > "2015/01/01"|<range:update gt="2015-01-01">
+
+# Timestamps yyyy/mm/dd hh
+created_on < "2015/01/01 12"|<range:creation lt="2015-01-01 12:00:00">
+created_on ≤ "2015/01/01 12"|<range:creation lte="2015-01-01 12:00:00">
+created_on = "2015/01/01 12"|<range:creation gte="2015-01-01 12:00:00" lt="2015-01-01 13:00:00">
+created_on ≥ "2015/01/01 12"|<range:creation gte="2015-01-01 12:00:00">
+created_on > "2015/01/01 12"|<range:creation gt="2015-01-01 12:00:00">
+updated_on < "2015/01/01 12"|<range:update lt="2015-01-01 12:00:00">
+updated_on ≤ "2015/01/01 12"|<range:update lte="2015-01-01 12:00:00">
+updated_on = "2015/01/01 12"|<range:update gte="2015-01-01 12:00:00" lt="2015-01-01 13:00:00">
+updated_on ≥ "2015/01/01 12"|<range:update gte="2015-01-01 12:00:00">
+updated_on > "2015/01/01 12"|<range:update gt="2015-01-01 12:00:00">
+created_at > "2015/01/01 12"|<range:creation gt="2015-01-01 12:00:00">
+updated_at > "2015/01/01 12"|<range:update gt="2015-01-01 12:00:00">
+
+# Timestamps yyyy/mm/dd hh:mm
+created_on < "2015/01/01 12.34"|<range:creation lt="2015-01-01 12:34:00">
+created_on ≤ "2015/01/01 12.34"|<range:creation lte="2015-01-01 12:34:00">
+created_on = "2015/01/01 12.34"|<range:creation gte="2015-01-01 12:34:00" lt="2015-01-01 12:35:00">
+created_on ≥ "2015/01/01 12.34"|<range:creation gte="2015-01-01 12:34:00">
+created_on > "2015/01/01 12.34"|<range:creation gt="2015-01-01 12:34:00">
+updated_on < "2015/01/01 12.34"|<range:update lt="2015-01-01 12:34:00">
+updated_on ≤ "2015/01/01 12.34"|<range:update lte="2015-01-01 12:34:00">
+updated_on = "2015/01/01 12.34"|<range:update gte="2015-01-01 12:34:00" lt="2015-01-01 12:35:00">
+updated_on ≥ "2015/01/01 12.34"|<range:update gte="2015-01-01 12:34:00">
+updated_on > "2015/01/01 12.34"|<range:update gt="2015-01-01 12:34:00">
+created_at > "2015/01/01 12.34"|<range:creation gt="2015-01-01 12:34:00">
+updated_at > "2015/01/01 12.34"|<range:update gt="2015-01-01 12:34:00">
+
+# Timestamps yyyy/mm/dd hh.mm.ss
+created_on < "2015/01/01 12.34.56"|<range:creation lt="2015-01-01 12:34:56">
+created_on ≤ "2015/01/01 12.34.56"|<range:creation lte="2015-01-01 12:34:56">
+created_on = "2015/01/01 12.34.56"|(<creation> == <value:"2015-01-01 12:34:56">)
+created_on ≥ "2015/01/01 12.34.56"|<range:creation gte="2015-01-01 12:34:56">
+created_on > "2015/01/01 12.34.56"|<range:creation gt="2015-01-01 12:34:56">
+updated_on < "2015/01/01 12.34.56"|<range:update lt="2015-01-01 12:34:56">
+updated_on ≤ "2015/01/01 12.34.56"|<range:update lte="2015-01-01 12:34:56">
+updated_on = "2015/01/01 12.34.56"|(<update> == <value:"2015-01-01 12:34:56">)
+updated_on ≥ "2015/01/01 12.34.56"|<range:update gte="2015-01-01 12:34:56">
+updated_on > "2015/01/01 12.34.56"|<range:update gt="2015-01-01 12:34:56">
+created_at > "2015/01/01 12.34.56"|<range:creation gt="2015-01-01 12:34:56">
+updated_at > "2015/01/01 12.34.56"|<range:update gt="2015-01-01 12:34:56">
+
+# timestamps missing zeros
+created_on = "2015/1/2 1.3.5"|(<creation> == <value:"2015-01-02 01:03:05">)
+
 
 # Flag matcher
 flag.foo:true|<flag:foo set>