[DDC-1014] Add Date Diff, Add and Sub Support for MySQL, SQLite, PostgreSQL and Oracle.

lib/Doctrine/DBAL/Platforms/MySqlPlatform.php

@@ -99,6 +99,31 @@ class MySqlPlatform extends AbstractPlatform
         return 'CONCAT(' . join(', ', (array) $args) . ')';
     }
 
+    public function getDateDiffExpression($date1, $date2)
+    {
+        return 'DATEDIFF(' . $date1 . ', ' . $date2 . ')';
+    }
+
+    public function getDateAddDaysExpression($date, $days)
+    {
+        return 'DATE_ADD(' . $date . ', INTERVAL ' . (int)$days . ' DAY)';
+    }
+
+    public function getDateSubDaysExpression($date, $days)
+    {
+        return 'DATE_SUB(' . $date . ', INTERVAL ' . (int)$days . ' DAY)';
+    }
+
+    public function getDateAddMonthExpression($date, $months)
+    {
+        return 'DATE_ADD(' . $date . ', INTERVAL ' . (int)$months . ' MONTH)';
+    }
+
+    public function getDateSubMonthExpression($date, $months)
+    {
+        return 'DATE_SUB(' . $date . ', INTERVAL ' . (int)$months . ' MONTH)';
+    }
+
     public function getListDatabasesSQL()
     {
         return 'SHOW DATABASES';

lib/Doctrine/DBAL/Platforms/OraclePlatform.php

@@ -99,6 +99,31 @@ class OraclePlatform extends AbstractPlatform
     {
         return 'SYS_GUID()';
     }
+
+    public function getDateDiffExpression($date1, $date2)
+    {
+        return '('.$date1 . '-'.$date2.')';
+    }
+
+    public function getDateAddDaysExpression($date, $days)
+    {
+        return '(' . $date . '+' . (int)$days . ')';
+    }
+
+    public function getDateSubDaysExpression($date, $days)
+    {
+        return '(' . $date . '-' . (int)$days . ')';
+    }
+
+    public function getDateAddMonthExpression($date, $months)
+    {
+        return "ADD_MONTHS(" . $date . ", " . (int)$months . ")";
+    }
+
+    public function getDateSubMonthExpression($date, $months)
+    {
+        return "ADD_MONTHS(" . $date . ", -" . (int)$months . ")";
+    }
     
     /**
      * Gets the SQL used to create a sequence that starts with a given value

lib/Doctrine/DBAL/Platforms/PostgreSqlPlatform.php

@@ -91,6 +91,31 @@ class PostgreSqlPlatform extends AbstractPlatform
             return 'POSITION('.$substr.' IN '.$str.')';
         }
     }
+
+    public function getDateDiffExpression($date1, $date2)
+    {
+        return '('.$date1 . '-'.$date2.')';
+    }
+
+    public function getDateAddDaysExpression($date, $days)
+    {
+        return "(" . $date . "+ interval '" . (int)$days . " day')";
+    }
+
+    public function getDateSubDaysExpression($date, $days)
+    {
+        return "(" . $date . "- interval '" . (int)$days . " day')";
+    }
+
+    public function getDateAddMonthExpression($date, $months)
+    {
+        return "(" . $date . "+ interval '" . (int)$months . " month')";
+    }
+
+    public function getDateSubMonthExpression($date, $months)
+    {
+        return "(" . $date . "- interval '" . (int)$months . " month')";
+    }
     
     /**
      * parses a literal boolean value and returns

lib/Doctrine/DBAL/Platforms/SqlitePlatform.php

@@ -125,6 +125,31 @@ class SqlitePlatform extends AbstractPlatform
         }
     }
 
+    public function getDateDiffExpression($date1, $date2)
+    {
+        return 'ROUND(JULIANDAY('.$date1 . ')-JULIANDAY('.$date2.'))';
+    }
+
+    public function getDateAddDaysExpression($date, $days)
+    {
+        return "DATE(" . $date . ",'+". (int)$days . " day')";
+    }
+
+    public function getDateSubDaysExpression($date, $days)
+    {
+        return "DATE(" . $date . ",'-". (int)$days . " day')";
+    }
+
+    public function getDateAddMonthExpression($date, $months)
+    {
+        return "DATE(" . $date . ",'+". (int)$months . " month')";
+    }
+
+    public function getDateSubMonthExpression($date, $months)
+    {
+        return "DATE(" . $date . ",'-". (int)$months . " month')";
+    }
+
     protected function _getTransactionIsolationLevelSQL($level)
     {
         switch ($level) {

tests/Doctrine/Tests/DBAL/Functional/DataAccessTest.php

@@ -244,4 +244,27 @@ class DataAccessTest extends \Doctrine\Tests\DbalFunctionalTestCase
         $this->assertEquals(5, count($data));
         $this->assertEquals(array(array(100), array(101), array(102), array(103), array(104)), $data);
     }
+
+    /**
+     * @group DDC-1014
+     */
+    public function testDateArithmetics()
+    {
+        $p = $this->_conn->getDatabasePlatform();
+        $sql = 'SELECT ';
+        $sql .= $p->getDateDiffExpression('test_datetime', "'2010-12-24 12:00:00'") .' AS diff, ';
+        $sql .= $p->getDateAddDaysExpression('test_datetime', 10) .' AS add_days, ';
+        $sql .= $p->getDateSubDaysExpression('test_datetime', 10) .' AS sub_days, ';
+        $sql .= $p->getDateAddMonthExpression('test_datetime', 2) .' AS add_month, ';
+        $sql .= $p->getDateSubMonthExpression('test_datetime', 2) .' AS sub_month ';
+        $sql .= 'FROM fetch_table';
+
+        $row = $this->_conn->fetchAssoc($sql);
+
+        $this->assertEquals(-357, (int)$row['diff'], "Date difference should be -356 days.");
+        $this->assertEquals('2010-01-11', date('Y-m-d', strtotime($row['add_days'])), "Adding date should end up on 2010-01-11");
+        $this->assertEquals('2009-12-22', date('Y-m-d', strtotime($row['sub_days'])), "Subtracting date should end up on 2009-12-22");
+        $this->assertEquals('2010-03-01', date('Y-m-d', strtotime($row['add_month'])), "Adding month should end up on 2010-03-01");
+        $this->assertEquals('2009-11-01', date('Y-m-d', strtotime($row['sub_month'])), "Adding month should end up on 2009-11-01");
+    }
 }
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