Implementing a basic Dialects system and a way for them to translate a

query object to the target driver

lib/Cake/Model/Datasource/Database/Dialect/PostgresDialect.php

@@ -0,0 +1,26 @@
+<?php
+/**
+ * 
+ * PHP Version 5.4
+ *
+ * CakePHP(tm) Tests <http://book.cakephp.org/2.0/en/development/testing.html>
+ * Copyright 2005-2012, Cake Software Foundation, Inc. (http://cakefoundation.org)
+ *
+ * Licensed under The Open Group Test Suite License
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright 2005-2013, Cake Software Foundation, Inc. (http://cakefoundation.org)
+ * @link          http://book.cakephp.org/2.0/en/development/testing.html CakePHP(tm) Tests
+ * @package       Cake.Test.Case.Model.Datasource.Database
+ * @since         CakePHP(tm) v 3.0
+ * @license       MIT License (http://www.opensource.org/licenses/mit-license.php)
+ */
+namespace Cake\Model\Datasource\Database\Dialect;
+
+trait PostgresDialect {
+
+	protected function _selectQueryTranslator($query) {
+		return $query;
+	}
+
+}

lib/Cake/Model/Datasource/Database/Driver.php

@@ -2,26 +2,16 @@
 
 namespace Cake\Model\Datasource\Database;
 
+use \Cake\Model\Datasource\Database\SqlDialect;
+
 /**
  * Represents a database diver containing all specificities for
  * a database engine including its SQL dialect
  *
  **/
 abstract class Driver {
 
-/**
- *  String used to start a database identifier quoting to make it safe
- *
- * @var string
- **/
-	public $startQuote = '"';
-
-/**
- * String used to end a database identifier quoting to make it safe
- *
- * @var string
- **/
-	public $endQuote = '"';
+	use SqlDialect;
 
 /**
  * Establishes a connection to the database server
@@ -40,10 +30,9 @@ public abstract function disconnect();
 
 /**
  * Returns correct connection resource or object that is internally used
- * If first argument is passed, it will set internal conenction object or
- * result to the value passed
+ * If first argument is passed, 
  *
- * @return mixed connection object used internally
+ * @return void
  **/
 	public abstract function connection($connection = null);
 
@@ -130,49 +119,6 @@ public function rollbackSavePointSQL($name) {
  **/
 	public abstract function quote($value, $type);
 
-/**
- * Quotes a database identifier (a column name, table name, etc..) to
- * be used safely in queries without the risk of using reserver words
- *
- * @param string $identifier
- * @return string
- **/
-	public function quoteIdentifier($identifier) {
-		$identifier = trim($identifier);
-
-		if ($identifier === '*') {
-			return '*';
-		}
-
-		if (preg_match('/^[\w-]+(?:\.[^ \*]*)*$/', $identifier)) { // string, string.string
-			if (strpos($identifier, '.') === false) { // string
-				return $this->startQuote . $identifier . $this->endQuote;
-			}
-			$items = explode('.', $identifier);
-			return $this->startQuote . implode($this->endQuote . '.' . $this->startQuote, $items) . $this->endQuote;
-		}
-
-		if (preg_match('/^[\w-]+\.\*$/', $identifier)) { // string.*
-			return $this->startQuote . str_replace('.*', $this->endQuote . '.*', $identifier);
-		}
-
-		if (preg_match('/^([\w-]+)\((.*)\)$/', $identifier, $matches)) { // Functions
-			return $matches[1] . '(' . $this->quoteIdentifier($matches[2]) . ')';
-		}
-
-		if (preg_match('/^([\w-]+(\.[\w-]+|\(.*\))*)\s+AS\s*([\w-]+)$/i', $identifier, $matches)) {
-			return preg_replace(
-				'/\s{2,}/', ' ', $this->quoteIdentifier($matches[1]) . ' AS  ' . $this->quoteIdentifier($matches[3])
-			);
-		}
-
-		if (preg_match('/^[\w-_\s]*[\w-_]+/', $identifier)) {
-			return $this->startQuote . $identifier . $this->endQuote;
-		}
-
-		return $identifier;
-	}
-
 /**
  * Returns last id generated for a table or sequence in database
  *

lib/Cake/Model/Datasource/Database/Driver/Postgres.php

@@ -1,13 +1,30 @@
 <?php
-
+/**
+ * 
+ * PHP Version 5.4
+ *
+ * CakePHP(tm) Tests <http://book.cakephp.org/2.0/en/development/testing.html>
+ * Copyright 2005-2012, Cake Software Foundation, Inc. (http://cakefoundation.org)
+ *
+ * Licensed under The Open Group Test Suite License
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright 2005-2013, Cake Software Foundation, Inc. (http://cakefoundation.org)
+ * @link          http://book.cakephp.org/2.0/en/development/testing.html CakePHP(tm) Tests
+ * @package       Cake.Test.Case.Model.Datasource.Database
+ * @since         CakePHP(tm) v 3.0
+ * @license       MIT License (http://www.opensource.org/licenses/mit-license.php)
+ */
 namespace Cake\Model\Datasource\Database\Driver;
 
 use Cake\Model\Datasource\Database\Statement;
+use Cake\Model\Datasource\Database\Dialect\PostgresDialect;
 use PDO;
 
 class Postgres extends \Cake\Model\Datasource\Database\Driver {
 
 	use PDODriver { connect as protected _connect; }
+	use PostgresDialect;
 
 /**
  * Base configuration settings for Postgres driver

lib/Cake/Model/Datasource/Database/Query.php

@@ -116,7 +116,11 @@ public function sql() {
 			return $sql .= $this->{'_build' . ucFirst($name) . 'Part'}($parts, $sql);
 		};
 
-		$this->build($builder);
+		// TODO: Should Query actually get the driver or just let the connection decide where
+		// to get the query translator?
+		$translator = $this->connection()->driver()->queryTranslator($this->_type);
+		$query = $translator($this);
+		$query->build($builder->bindTo($query));
 		return $sql;
 	}
 

lib/Cake/Model/Datasource/Database/SQLDialect.php

@@ -0,0 +1,95 @@
+<?php
+/**
+ * 
+ * PHP Version 5.4
+ *
+ * CakePHP(tm) Tests <http://book.cakephp.org/2.0/en/development/testing.html>
+ * Copyright 2005-2012, Cake Software Foundation, Inc. (http://cakefoundation.org)
+ *
+ * Licensed under The Open Group Test Suite License
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright 2005-2013, Cake Software Foundation, Inc. (http://cakefoundation.org)
+ * @link          http://book.cakephp.org/2.0/en/development/testing.html CakePHP(tm) Tests
+ * @package       Cake.Test.Case.Model.Datasource.Database
+ * @since         CakePHP(tm) v 3.0
+ * @license       MIT License (http://www.opensource.org/licenses/mit-license.php)
+ */
+namespace Cake\Model\Datasource\Database;
+
+trait SQLDialect {
+
+/**
+ *  String used to start a database identifier quoting to make it safe
+ *
+ * @var string
+ **/
+	public $startQuote = '"';
+
+/**
+ * String used to end a database identifier quoting to make it safe
+ *
+ * @var string
+ **/
+	public $endQuote = '"';
+
+/**
+ * Quotes a database identifier (a column name, table name, etc..) to
+ * be used safely in queries without the risk of using reserver words
+ *
+ * @param string $identifier
+ * @return string
+ **/
+	public function quoteIdentifier($identifier) {
+		$identifier = trim($identifier);
+
+		if ($identifier === '*') {
+			return '*';
+		}
+
+		if (preg_match('/^[\w-]+(?:\.[^ \*]*)*$/', $identifier)) { // string, string.string
+			if (strpos($identifier, '.') === false) { // string
+				return $this->startQuote . $identifier . $this->endQuote;
+			}
+			$items = explode('.', $identifier);
+			return $this->startQuote . implode($this->endQuote . '.' . $this->startQuote, $items) . $this->endQuote;
+		}
+
+		if (preg_match('/^[\w-]+\.\*$/', $identifier)) { // string.*
+			return $this->startQuote . str_replace('.*', $this->endQuote . '.*', $identifier);
+		}
+
+		if (preg_match('/^([\w-]+)\((.*)\)$/', $identifier, $matches)) { // Functions
+			return $matches[1] . '(' . $this->quoteIdentifier($matches[2]) . ')';
+		}
+
+		if (preg_match('/^([\w-]+(\.[\w-]+|\(.*\))*)\s+AS\s*([\w-]+)$/i', $identifier, $matches)) {
+			return preg_replace(
+				'/\s{2,}/', ' ', $this->quoteIdentifier($matches[1]) . ' AS  ' . $this->quoteIdentifier($matches[3])
+			);
+		}
+
+		if (preg_match('/^[\w-_\s]*[\w-_]+/', $identifier)) {
+			return $this->startQuote . $identifier . $this->endQuote;
+		}
+
+		return $identifier;
+	}
+
+	public function queryTranslator($type) {
+		return function($query) use ($type) {
+			return $this->{'_' . $type . 'QueryTranslator'}($query);
+		};
+	}
+
+	protected function _selectQueryTranslator($query) {
+		if (is_array($query->clause('distinct'))) {
+			$query->group($query->clause('distinct'), true);
+			$query->distinct(false);
+		}
+
+		return $query;
+	}
+
+}
+