Postgres: substring('foobar' from 2 for 3)

core/OSQL/SQLFunction.class.php

@@ -24,6 +24,7 @@ final class SQLFunction extends Castable implements MappableObject, Aliased
 		private $aggregate	= null;
 
 		private $args	= array();
+		private $joiners = array();
 
 		/**
 		 * @return SQLFunction
@@ -94,6 +95,25 @@ public function setAggregateDistinct()
 			return $this;
 		}
 
+		/**
+		 * @return SQLFunction
+		**/
+		public function setJoiner($joiner, $index = 0)
+		{
+			$this->joiners[$index] = $joiner;
+
+			return $this;
+		}
+
+		public function getJoiner($index)
+		{
+			if (array_key_exists($index, $this->joiners)) {
+				return $this->joiners[$index];
+			} else {
+				return ', ';
+			}
+		}
+
 		/**
 		 * @return SQLFunction
 		**/
@@ -111,10 +131,14 @@ public function toMapped(ProtoDAO $dao, JoinCapableQuery $query)
 			}
 
 			$sqlFunction = call_user_func_array(array('self', 'create'), $mapped);
+			/* @var $sqlFunction SQLFunction */
 
 			$sqlFunction->aggregate = $this->aggregate;
 
 			$sqlFunction->castTo($this->cast);
+			foreach ($this->joiners as $index => $joiner) {
+				$sqlFunction->setJoiner($joiner, $index);
+			}
 
 			return $sqlFunction;
 		}
@@ -151,7 +175,7 @@ public function toDialectString(Dialect $dialect)
 				$out .= 'DISTINCT ';
 			}
 
-			$out .= ($args == array() ? null : implode(', ', $args)).')';
+			$out .= ($args == array() ? null : $this->joinArgs($args)).')';
 
 			$out =
 				$this->cast
@@ -163,5 +187,22 @@ public function toDialectString(Dialect $dialect)
 					? $out.' AS '.$dialect->quoteTable($this->alias)
 					: $out;
 		}
+
+		private function joinArgs(array $args) {
+			if (count($args) == 0) {
+				return '';
+			} elseif (count($this->joiners) == 0) {
+				return implode(', ', $args);
+			} else {
+				$joinedArgs = '';
+				for ($i = 0; $i < count($args); $i++) {
+					$joinedArgs .= $args[$i];
+					if ($i < count($args) - 1) {
+						$joinedArgs .= ' ' . $this->getJoiner($i) . ' ';
+					}
+				}
+				return $joinedArgs;
+			}
+		}
 	}
 ?>

test/main/CriteriaTest.class.php

@@ -214,6 +214,33 @@ public function testDialectStringObjects()
 			);
 		}
 
+		public function testSqlFunction()
+		{
+			$criteria =
+				Criteria::create(TestCity::dao())->
+				addProjection(
+					Projection::property(
+						SQLFunction::create(
+							'count',
+							SQLFunction::create(
+								'substring',
+								'name',
+								DBValue::create('M....w'),
+								DBValue::create('#')
+							)->
+							setJoiner('from')->
+							setJoiner('for', 1)
+						)
+						->setAggregateDistinct()
+					)
+				);
+
+			$this->assertEquals(
+				$criteria->toDialectString(PostgresDialect::me()),
+				'SELECT count(DISTINCT substring("custom_table"."name" from \'M....w\' for \'#\')) FROM "custom_table"'
+			);
+		}
+
 		public function testSleepWithEmptyDao()
 		{
 			$baseCriteria =
@@ -258,6 +285,8 @@ public function testForgottenDao()
 				$this->fail();
 			} catch (WrongStateException $e) {/*it's good*/}
 		}
+
+//		public function
 
 		public static function orderDataProvider()
 		{

test/main/OsqlSelectTest.class.php

@@ -16,7 +16,16 @@ public function testSelectGet()
 					SQLFunction::create(
 						'count', DBField::create('field5', 'test_table')
 					)->
+					setAggregateDistinct()->
 					setAlias('alias5')
+				)->
+				get(
+					SQLFunction::create(
+						'substring',
+						DBField::create('field6', 'test_table'),
+						DBValue::create('a..b')
+					)->
+					setJoiner('from', 0)
 				);
 
 			$this->assertEquals(
@@ -26,7 +35,8 @@ public function testSelectGet()
 					.'"test_table"."field2", '
 					.'"test_table"."field3" AS "alias3", '
 					.'"test_table"."field4", '
-					.'count("test_table"."field5") AS "alias5" '
+					.'count(DISTINCT "test_table"."field5") AS "alias5", '
+					.'substring("test_table"."field6" from \'a..b\') '
 				.'FROM "test_table"'
 			);
 		}