Added JDatabaseQuery function to extract part of timestamp.

libraries/joomla/database/query.php

@@ -723,6 +723,108 @@ public function from($tables)
 		return $this;
 	}
 
+	/**
+	 * Used to get a string to extract year from date column.
+	 *
+	 * Usage:
+	 * $query->select($query->year($query->quoteName('dateColumn')));
+	 * 
+	 * @param   string  $date  Date column containing year to be extracted.
+	 *
+	 * @return  string  Returns string to extract year from a date.
+	 *
+	 * @since   12.1
+	 */
+	public function year($date)
+	{
+		return 'YEAR(' . $date . ')';
+	}
+
+	/**
+	 * Used to get a string to extract month from date column.
+	 *
+	 * Usage:
+	 * $query->select($query->month($query->quoteName('dateColumn')));
+	 * 
+	 * @param   string  $date  Date column containing month to be extracted.
+	 *
+	 * @return  string  Returns string to extract month from a date.
+	 *
+	 * @since   12.1
+	 */
+	public function month($date)
+	{
+		return 'MONTH(' . $date . ')';
+	}
+
+	/**
+	 * Used to get a string to extract day from date column.
+	 *
+	 * Usage:
+	 * $query->select($query->day($query->quoteName('dateColumn')));
+	 * 
+	 * @param   string  $date  Date column containing day to be extracted.
+	 *
+	 * @return  string  Returns string to extract day from a date.
+	 *
+	 * @since   12.1
+	 */
+	public function day($date)
+	{
+		return 'DAY(' . $date . ')';
+	}
+
+	/**
+	 * Used to get a string to extract hour from date column.
+	 *
+	 * Usage:
+	 * $query->select($query->hour($query->quoteName('dateColumn')));
+	 * 
+	 * @param   string  $date  Date column containing hour to be extracted.
+	 *
+	 * @return  string  Returns string to extract hour from a date.
+	 *
+	 * @since   12.1
+	 */
+	public function hour($date)
+	{
+		return 'HOUR(' . $date . ')';
+	}
+
+	/**
+	 * Used to get a string to extract minute from date column.
+	 *
+	 * Usage:
+	 * $query->select($query->minute($query->quoteName('dateColumn')));
+	 * 
+	 * @param   string  $date  Date column containing minute to be extracted.
+	 *
+	 * @return  string  Returns string to extract minute from a date.
+	 *
+	 * @since   12.1
+	 */
+	public function minute($date)
+	{
+		return 'MINUTE(' . $date . ')';
+	}
+
+	/**
+	 * Used to get a string to extract seconds from date column.
+	 *
+	 * Usage:
+	 * $query->select($query->second($query->quoteName('dateColumn')));
+	 * 
+	 * @param   string  $date  Date column containing second to be extracted.
+	 *
+	 * @return  string  Returns string to extract second from a date.
+	 *
+	 * @since   12.1
+	 */
+	public function second($date)
+	{
+		return 'SECOND(' . $date . ')';
+	}
+
 	/**
 	 * Add a grouping column to the GROUP clause of the query.
 	 *

tests/suite/joomla/database/JDatabaseQueryTest.php

@@ -123,6 +123,120 @@ public function test__call()
 		);
 	}
 
+	/**
+	 * Test for year extraction from date.
+	 *
+	 * @return  void
+	 *
+	 * @since   12.1
+	 */
+	public function test__toStringYear()
+	{
+		$q = new JDatabaseQueryInspector($this->dbo);
+
+		$q->select($q->year($q->quoteName('col')))->from('table');
+
+		$this->assertThat(
+					(string) $q,
+					$this->equalTo("\nSELECT YEAR(`col`)\nFROM table")
+		);
+	}
+
+	/**
+	 * Test for month extraction from date.
+	 *
+	 * @return  void
+	 *
+	 * @since   12.1
+	 */
+	public function test__toStringMonth()
+	{
+		$q = new JDatabaseQueryInspector($this->dbo);
+
+		$q->select($q->month($q->quoteName('col')))->from('table');
+
+		$this->assertThat(
+					(string) $q,
+					$this->equalTo("\nSELECT MONTH(`col`)\nFROM table")
+		);
+	}
+
+	/**
+	 * Test for day extraction from date.
+	 *
+	 * @return  void
+	 *
+	 * @since   12.1
+	 */
+	public function test__toStringDay()
+	{
+		$q = new JDatabaseQueryInspector($this->dbo);
+
+		$q->select($q->day($q->quoteName('col')))->from('table');
+
+		$this->assertThat(
+					(string) $q,
+					$this->equalTo("\nSELECT DAY(`col`)\nFROM table")
+		);
+	}
+
+	/**
+	 * Test for hour extraction from date.
+	 *
+	 * @return  void
+	 *
+	 * @since   12.1
+	 */
+	public function test__toStringHour()
+	{
+		$q = new JDatabaseQueryInspector($this->dbo);
+
+		$q->select($q->hour($q->quoteName('col')))->from('table');
+
+		$this->assertThat(
+					(string) $q,
+					$this->equalTo("\nSELECT HOUR(`col`)\nFROM table")
+		);
+	}
+
+	/**
+	 * Test for minute extraction from date.
+	 *
+	 * @return  void
+	 *
+	 * @since   12.1
+	 */
+	public function test__toStringMinute()
+	{
+		$q = new JDatabaseQueryInspector($this->dbo);
+
+		$q->select($q->minute($q->quoteName('col')))->from('table');
+
+		$this->assertThat(
+					(string) $q,
+					$this->equalTo("\nSELECT MINUTE(`col`)\nFROM table")
+		);
+	}
+
+	/**
+	 * Test for seconds extraction from date.
+	 *
+	 * @return  void
+	 *
+	 * @since   12.1
+	 */
+	public function test__toStringSecond()
+	{
+		$q = new JDatabaseQueryInspector($this->dbo);
+
+		$q->select($q->second($q->quoteName('col')))->from('table');
+
+		$this->assertThat(
+					(string) $q,
+					$this->equalTo("\nSELECT SECOND(`col`)\nFROM table")
+		);
+	}
+
 	/**
 	 * Test for the JDatabaseQuery::__string method for a 'select' case.
 	 *