From 2c9399a78aa6b272311a826bb75d141674bb9566 Mon Sep 17 00:00:00 2001
From: Juan Basso <jrbasso@gmail.com>
Date: Sat, 31 Mar 2012 21:58:33 -0400
Subject: [PATCH 01/10] Removed unused attribute and moved getVersion to be
 reused in all PDO drivers.

---
 lib/Cake/Model/Datasource/Database/Mysql.php  | 20 -----------------
 .../Model/Datasource/Database/Postgres.php    | 11 ----------
 .../Model/Datasource/Database/Sqlserver.php   | 22 +------------------
 lib/Cake/Model/Datasource/DboSource.php       | 22 +++++++++----------
 4 files changed, 11 insertions(+), 64 deletions(-)

diff --git a/lib/Cake/Model/Datasource/Database/Mysql.php b/lib/Cake/Model/Datasource/Database/Mysql.php
index b5421f43d..17da3224b 100644
--- a/lib/Cake/Model/Datasource/Database/Mysql.php
+++ b/lib/Cake/Model/Datasource/Database/Mysql.php
@@ -77,17 +77,6 @@ class Mysql extends DboSource {
  */
 	protected $_useAlias = true;
 
-/**
- * Index of basic SQL commands
- *
- * @var array
- */
-	protected $_commands = array(
-		'begin'    => 'START TRANSACTION',
-		'commit'   => 'COMMIT',
-		'rollback' => 'ROLLBACK'
-	);
-
 /**
  * List of engine specific additional field parameters used on table creating
  *
@@ -262,15 +251,6 @@ class Mysql extends DboSource {
 		return $this->_execute('SHOW VARIABLES LIKE ?', array('character_set_client'))->fetchObject()->Value;
 	}
 
-/**
- * Gets the version string of the database server
- *
- * @return string The database encoding
- */
-	public function getVersion() {
-		return $this->_connection->getAttribute(PDO::ATTR_SERVER_VERSION);
-	}
-
 /**
  * Query charset by collation
  *
diff --git a/lib/Cake/Model/Datasource/Database/Postgres.php b/lib/Cake/Model/Datasource/Database/Postgres.php
index 064a1cca4..29f6bbe2c 100644
--- a/lib/Cake/Model/Datasource/Database/Postgres.php
+++ b/lib/Cake/Model/Datasource/Database/Postgres.php
@@ -33,17 +33,6 @@ class Postgres extends DboSource {
  */
 	public $description = "PostgreSQL DBO Driver";
 
-/**
- * Index of basic SQL commands
- *
- * @var array
- */
-	protected $_commands = array(
-		'begin'    => 'BEGIN',
-		'commit'   => 'COMMIT',
-		'rollback' => 'ROLLBACK'
-	);
-
 /**
  * Base driver configuration settings.  Merged with user settings.
  *
diff --git a/lib/Cake/Model/Datasource/Database/Sqlserver.php b/lib/Cake/Model/Datasource/Database/Sqlserver.php
index d7882663b..adea9beb1 100644
--- a/lib/Cake/Model/Datasource/Database/Sqlserver.php
+++ b/lib/Cake/Model/Datasource/Database/Sqlserver.php
@@ -98,31 +98,12 @@ class Sqlserver extends DboSource {
 		'boolean'	=> array('name' => 'bit')
 	);
 
-/**
- * Index of basic SQL commands
- *
- * @var array
- */
-	protected $_commands = array(
-		'begin'    => 'BEGIN TRANSACTION',
-		'commit'   => 'COMMIT',
-		'rollback' => 'ROLLBACK'
-	);
-
 /**
  * Magic column name used to provide pagination support for SQLServer 2008
  * which lacks proper limit/offset support.
  */
 	const ROW_COUNTER = '_cake_page_rownum_';
 
-/**
- * The version of SQLServer being used.  If greater than 11
- * Normal limit offset statements will be used
- *
- * @var string
- */
-	protected $_version;
-
 /**
  * Connects to the database using options in the given configuration array.
  *
@@ -151,7 +132,6 @@ class Sqlserver extends DboSource {
 			throw new MissingConnectionException(array('class' => $e->getMessage()));
 		}
 
-		$this->_version = $this->_connection->getAttribute(PDO::ATTR_SERVER_VERSION);
 		return $this->connected;
 	}
 
@@ -515,7 +495,7 @@ class Sqlserver extends DboSource {
 				}
 
 				// For older versions use the subquery version of pagination.
-				if (version_compare($this->_version, '11', '<') && preg_match('/FETCH\sFIRST\s+([0-9]+)/i', $limit, $offset)) {
+				if (version_compare($this->getVersion(), '11', '<') && preg_match('/FETCH\sFIRST\s+([0-9]+)/i', $limit, $offset)) {
 					preg_match('/OFFSET\s*(\d+)\s*.*?(\d+)\s*ROWS/', $limit, $limitOffset);
 
 					$limit = 'TOP ' . intval($limitOffset[2]);
diff --git a/lib/Cake/Model/Datasource/DboSource.php b/lib/Cake/Model/Datasource/DboSource.php
index 7e85cc4bb..39a90c382 100644
--- a/lib/Cake/Model/Datasource/DboSource.php
+++ b/lib/Cake/Model/Datasource/DboSource.php
@@ -183,17 +183,6 @@ class DboSource extends DataSource {
  */
 	protected $_transactionNesting = 0;
 
-/**
- * Index of basic SQL commands
- *
- * @var array
- */
-	protected $_commands = array(
-		'begin' => 'BEGIN',
-		'commit' => 'COMMIT',
-		'rollback' => 'ROLLBACK'
-	);
-
 /**
  * Default fields that are used by the DBO
  *
@@ -294,12 +283,21 @@ class DboSource extends DataSource {
 /**
  * Get the underlying connection object.
  *
- * @return PDOConnection
+ * @return PDO
  */
 	public function getConnection() {
 		return $this->_connection;
 	}
 
+/**
+ * Gets the version string of the database server
+ *
+ * @return string The database version
+ */
+	public function getVersion() {
+		return $this->_connection->getAttribute(PDO::ATTR_SERVER_VERSION);
+	}
+
 /**
  * Returns a quoted and escaped string of $data for use in an SQL statement.
  *

From 2c1cf29aa3fda70ca314e6af023333552b96ab6d Mon Sep 17 00:00:00 2001
From: Juan Basso <jrbasso@gmail.com>
Date: Sat, 31 Mar 2012 22:39:18 -0400
Subject: [PATCH 02/10] Added real support to nested transactions for Mysql,
 Postgres, Sqlite.

---
 lib/Cake/Model/Datasource/Database/Mysql.php  |   9 ++
 .../Model/Datasource/Database/Postgres.php    |   9 ++
 lib/Cake/Model/Datasource/Database/Sqlite.php |   9 ++
 lib/Cake/Model/Datasource/DboSource.php       | 113 ++++++++++++++----
 4 files changed, 118 insertions(+), 22 deletions(-)

diff --git a/lib/Cake/Model/Datasource/Database/Mysql.php b/lib/Cake/Model/Datasource/Database/Mysql.php
index 17da3224b..ad618429a 100644
--- a/lib/Cake/Model/Datasource/Database/Mysql.php
+++ b/lib/Cake/Model/Datasource/Database/Mysql.php
@@ -676,4 +676,13 @@ class Mysql extends DboSource {
 		return $this->config['database'];
 	}
 
+/**
+ * Check if the server support nested transactions
+ *
+ * @return boolean
+ */
+	protected function _supportNestedTransaction() {
+		return version_compare($this->getVersion(), '4.1', '>=');
+	}
+
 }
diff --git a/lib/Cake/Model/Datasource/Database/Postgres.php b/lib/Cake/Model/Datasource/Database/Postgres.php
index 29f6bbe2c..d681c8a64 100644
--- a/lib/Cake/Model/Datasource/Database/Postgres.php
+++ b/lib/Cake/Model/Datasource/Database/Postgres.php
@@ -895,4 +895,13 @@ class Postgres extends DboSource {
 		return $this->config['schema'];
 	}
 
+/**
+ * Check if the server support nested transactions
+ *
+ * @return boolean
+ */
+	protected function _supportNestedTransaction() {
+		return version_compare($this->getVersion(), '8.0', '>=');
+	}
+
 }
diff --git a/lib/Cake/Model/Datasource/Database/Sqlite.php b/lib/Cake/Model/Datasource/Database/Sqlite.php
index 59db71dcf..3eee31a54 100644
--- a/lib/Cake/Model/Datasource/Database/Sqlite.php
+++ b/lib/Cake/Model/Datasource/Database/Sqlite.php
@@ -559,4 +559,13 @@ class Sqlite extends DboSource {
 		return "main"; // Sqlite Datasource does not support multidb
 	}
 
+/**
+ * Check if the server support nested transactions
+ *
+ * @return boolean
+ */
+	protected function _supportNestedTransaction() {
+		return version_compare($this->getVersion(), '3.6.8', '>=');
+	}
+
 }
diff --git a/lib/Cake/Model/Datasource/DboSource.php b/lib/Cake/Model/Datasource/DboSource.php
index 39a90c382..47a6c2fd6 100644
--- a/lib/Cake/Model/Datasource/DboSource.php
+++ b/lib/Cake/Model/Datasource/DboSource.php
@@ -2017,6 +2017,15 @@ class DboSource extends DataSource {
 		return $this->execute('TRUNCATE TABLE ' . $this->fullTableName($table));
 	}
 
+/**
+ * Check if the server support nested transactions
+ *
+ * @return boolean
+ */
+	protected function _supportNestedTransaction() {
+		return false;
+	}
+
 /**
  * Begin a transaction
  *
@@ -2025,15 +2034,33 @@ class DboSource extends DataSource {
  * or a transaction has not started).
  */
 	public function begin() {
-		if ($this->_transactionStarted || $this->_connection->beginTransaction()) {
-			if ($this->fullDebug && empty($this->_transactionNesting)) {
-				$this->logQuery('BEGIN');
+		if ($this->_transactionStarted) {
+			if ($this->_supportNestedTransaction()) {
+				return $this->_beginNested();
 			}
-			$this->_transactionStarted = true;
 			$this->_transactionNesting++;
-			return true;
+			return $this->_transactionStarted;
 		}
-		return false;
+
+		$this->_transactionNesting = 0;
+		if ($this->fullDebug) {
+			$this->logQuery('BEGIN');
+		}
+		return $this->_transactionStarted = $this->_connection->beginTransaction();
+	}
+
+/**
+ * Begin a nested transaction
+ *
+ * @return boolean
+ */
+	protected function _beginNested() {
+		$query = 'SAVEPOINT LEVEL' . ++$this->_transactionNesting;
+		if ($this->fullDebug) {
+			$this->logQuery($query);
+		}
+		$this->_connection->exec($query);
+		return true;
 	}
 
 /**
@@ -2044,19 +2071,38 @@ class DboSource extends DataSource {
  * or a transaction has not started).
  */
 	public function commit() {
-		if ($this->_transactionStarted) {
-			$this->_transactionNesting--;
-			if ($this->_transactionNesting <= 0) {
-				$this->_transactionStarted = false;
-				$this->_transactionNesting = 0;
-				if ($this->fullDebug) {
-					$this->logQuery('COMMIT');
-				}
-				return $this->_connection->commit();
-			}
-			return true;
+		if (!$this->_transactionStarted) {
+			return false;
 		}
-		return false;
+
+		if ($this->_transactionNesting === 0) {
+			if ($this->fullDebug) {
+				$this->logQuery('COMMIT');
+			}
+			$this->_transactionStarted = false;
+			return $this->_connection->commit();
+		}
+
+		if ($this->_supportNestedTransaction()) {
+			return $this->_commitNested();
+		}
+
+		$this->_transactionNesting--;
+		return true;
+	}
+
+/**
+ * Commit a nested transaction
+ *
+ * @return boolean
+ */
+	protected function _commitNested() {
+		$query = 'RELEASE SAVEPOINT LEVEL' . $this->_transactionNesting--;
+		if ($this->fullDebug) {
+			$this->logQuery($query);
+		}
+		$this->_connection->exec($query);
+		return true;
 	}
 
 /**
@@ -2067,15 +2113,38 @@ class DboSource extends DataSource {
  * or a transaction has not started).
  */
 	public function rollback() {
-		if ($this->_transactionStarted && $this->_connection->rollBack()) {
+		if (!$this->_transactionStarted) {
+			return false;
+		}
+
+		if ($this->_transactionNesting === 0) {
 			if ($this->fullDebug) {
 				$this->logQuery('ROLLBACK');
 			}
 			$this->_transactionStarted = false;
-			$this->_transactionNesting = 0;
-			return true;
+			return $this->_connection->rollBack();
 		}
-		return false;
+
+		if ($this->_supportNestedTransaction()) {
+			return $this->_rollbackNested();
+		}
+
+		$this->_transactionNesting--;
+		return true;
+	}
+
+/**
+ * Rollback a nested transaction
+ *
+ * @return boolean
+ */
+	protected function _rollbackNested() {
+		$query = 'ROLLBACK TO SAVEPOINT LEVEL' . $this->_transactionNesting--;
+		if ($this->fullDebug) {
+			$this->logQuery($query);
+		}
+		$this->_connection->exec($query);
+		return true;
 	}
 
 /**

From 30258ac817e6494f3a75adc56710ec87b7bfa6dc Mon Sep 17 00:00:00 2001
From: Juan Basso <jrbasso@gmail.com>
Date: Sat, 31 Mar 2012 23:14:49 -0400
Subject: [PATCH 03/10] Added test for nested methods sequence.

---
 .../Case/Model/Datasource/DboSourceTest.php   | 29 +++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/lib/Cake/Test/Case/Model/Datasource/DboSourceTest.php b/lib/Cake/Test/Case/Model/Datasource/DboSourceTest.php
index 6c043a119..61d37b6bf 100644
--- a/lib/Cake/Test/Case/Model/Datasource/DboSourceTest.php
+++ b/lib/Cake/Test/Case/Model/Datasource/DboSourceTest.php
@@ -51,6 +51,10 @@ class DboTestSource extends DboSource {
 		$this->_connection = $conn;
 	}
 
+	protected function _supportNestedTransaction() {
+		return true;
+	}
+
 }
 
 /**
@@ -841,6 +845,31 @@ class DboSourceTest extends CakeTestCase {
 		$this->assertEquals($expected, $log['log'][0]);
 	}
 
+/**
+ * Test nested transaction calls
+ *
+ * @return void
+ */
+	public function testTransactionNested() {
+		$conn = $this->getMock('MockPDO');
+		$db = new DboTestSource();
+		$db->setConnection($conn);
+
+		$conn->expects($this->at(0))->method('beginTransaction')->will($this->returnValue(true));
+		$conn->expects($this->at(1))->method('exec')->with($this->equalTo('SAVEPOINT LEVEL1'))->will($this->returnValue(true));
+		$conn->expects($this->at(2))->method('exec')->with($this->equalTo('RELEASE SAVEPOINT LEVEL1'))->will($this->returnValue(true));
+		$conn->expects($this->at(3))->method('exec')->with($this->equalTo('SAVEPOINT LEVEL1'))->will($this->returnValue(true));
+		$conn->expects($this->at(4))->method('exec')->with($this->equalTo('ROLLBACK TO SAVEPOINT LEVEL1'))->will($this->returnValue(true));
+		$conn->expects($this->at(5))->method('commit')->will($this->returnValue(true));
+
+		$db->begin();
+		$db->begin();
+		$db->commit();
+		$db->begin();
+		$db->rollback();
+		$db->commit();
+	}
+
 /**
  * Test build statement with some fields missing
  *

From 22cd65b7d89b89ca306db6a08edfef328f2cbeae Mon Sep 17 00:00:00 2001
From: Juan Basso <jrbasso@gmail.com>
Date: Sun, 1 Apr 2012 00:01:11 -0400
Subject: [PATCH 04/10] Added tests in each datasource to test the nested
 transactions.

---
 .../Model/Datasource/Database/MysqlTest.php   | 38 ++++++++++++++++++-
 .../Datasource/Database/PostgresTest.php      | 35 +++++++++++++++++
 .../Model/Datasource/Database/SqliteTest.php  | 35 +++++++++++++++++
 3 files changed, 107 insertions(+), 1 deletion(-)

diff --git a/lib/Cake/Test/Case/Model/Datasource/Database/MysqlTest.php b/lib/Cake/Test/Case/Model/Datasource/Database/MysqlTest.php
index 3024a0607..a91069a60 100644
--- a/lib/Cake/Test/Case/Model/Datasource/Database/MysqlTest.php
+++ b/lib/Cake/Test/Case/Model/Datasource/Database/MysqlTest.php
@@ -45,7 +45,7 @@ class MysqlTest extends CakeTestCase {
 	public $fixtures = array(
 		'core.apple', 'core.article', 'core.articles_tag', 'core.attachment', 'core.comment',
 		'core.sample', 'core.tag', 'core.user', 'core.post', 'core.author', 'core.data_test',
-		'core.binary_test'
+		'core.binary_test', 'app.address'
 	);
 
 /**
@@ -3579,4 +3579,40 @@ class MysqlTest extends CakeTestCase {
 			->with("TRUNCATE TABLE `$schema`.`tbl_articles`");
 		$this->Dbo->truncate('articles');
 	}
+
+/**
+ * Test nested transaction
+ *
+ * @return void
+ */
+	public function testNestedTransaction() {
+		$obj = new ReflectionMethod($this->Dbo, '_supportNestedTransaction');
+		$obj->setAccessible(true);
+		$this->skipIf($obj->invoke($this->Dbo) === false, 'The MySQL server do not support nested transaction');
+
+		$this->loadFixtures('Address');
+		$model = ClassRegistry::init('Address');
+		$model->hasOne = $model->hasMany = $model->belongsTo = $model->hasAndBelongsToMany = array();
+		$model->cacheQueries = false;
+		$this->Dbo->cacheMethods = false;
+
+		$this->assertTrue($this->Dbo->begin());
+		$this->assertNotEmpty($model->read(null, 1));
+
+		$this->assertTrue($this->Dbo->begin());
+		$this->assertTrue($model->delete(1));
+		$this->assertEmpty($model->read(null, 1));
+		$this->assertTrue($this->Dbo->rollback());
+		$this->assertNotEmpty($model->read(null, 1));
+
+		$this->assertTrue($this->Dbo->begin());
+		$this->assertTrue($model->delete(1));
+		$this->assertEmpty($model->read(null, 1));
+		$this->assertTrue($this->Dbo->commit());
+		$this->assertEmpty($model->read(null, 1));
+
+		$this->assertTrue($this->Dbo->rollback());
+		$this->assertNotEmpty($model->read(null, 1));
+	}
+
 }
diff --git a/lib/Cake/Test/Case/Model/Datasource/Database/PostgresTest.php b/lib/Cake/Test/Case/Model/Datasource/Database/PostgresTest.php
index 54b331f48..4a6b7897e 100644
--- a/lib/Cake/Test/Case/Model/Datasource/Database/PostgresTest.php
+++ b/lib/Cake/Test/Case/Model/Datasource/Database/PostgresTest.php
@@ -909,4 +909,39 @@ class PostgresTest extends CakeTestCase {
 		$this->Dbo->truncate('articles');
 	}
 
+/**
+ * Test nested transaction
+ *
+ * @return void
+ */
+	public function testNestedTransaction() {
+		$obj = new ReflectionMethod($this->Dbo, '_supportNestedTransaction');
+		$obj->setAccessible(true);
+		$this->skipIf($obj->invoke($this->Dbo) === false, 'The Postgres server do not support nested transaction');
+
+		$this->loadFixtures('Article');
+		$model = new Article();
+		$model->hasOne = $model->hasMany = $model->belongsTo = $model->hasAndBelongsToMany = array();
+		$model->cacheQueries = false;
+		$this->Dbo->cacheMethods = false;
+
+		$this->assertTrue($this->Dbo->begin());
+		$this->assertNotEmpty($model->read(null, 1));
+
+		$this->assertTrue($this->Dbo->begin());
+		$this->assertTrue($model->delete(1));
+		$this->assertEmpty($model->read(null, 1));
+		$this->assertTrue($this->Dbo->rollback());
+		$this->assertNotEmpty($model->read(null, 1));
+
+		$this->assertTrue($this->Dbo->begin());
+		$this->assertTrue($model->delete(1));
+		$this->assertEmpty($model->read(null, 1));
+		$this->assertTrue($this->Dbo->commit());
+		$this->assertEmpty($model->read(null, 1));
+
+		$this->assertTrue($this->Dbo->rollback());
+		$this->assertNotEmpty($model->read(null, 1));
+	}
+
 }
diff --git a/lib/Cake/Test/Case/Model/Datasource/Database/SqliteTest.php b/lib/Cake/Test/Case/Model/Datasource/Database/SqliteTest.php
index f53257bff..1e4ed7e46 100644
--- a/lib/Cake/Test/Case/Model/Datasource/Database/SqliteTest.php
+++ b/lib/Cake/Test/Case/Model/Datasource/Database/SqliteTest.php
@@ -383,4 +383,39 @@ class SqliteTest extends CakeTestCase {
 		$this->assertTrue(Validation::uuid($result['Uuid']['id']), 'Not a uuid');
 	}
 
+/**
+ * Test nested transaction
+ *
+ * @return void
+ */
+	public function testNestedTransaction() {
+		$obj = new ReflectionMethod($this->Dbo, '_supportNestedTransaction');
+		$obj->setAccessible(true);
+		$this->skipIf($obj->invoke($this->Dbo) === false, 'The Sqlite version do not support nested transaction');
+
+		$this->loadFixtures('User');
+		$model = new User();
+		$model->hasOne = $model->hasMany = $model->belongsTo = $model->hasAndBelongsToMany = array();
+		$model->cacheQueries = false;
+		$this->Dbo->cacheMethods = false;
+
+		$this->assertTrue($this->Dbo->begin());
+		$this->assertNotEmpty($model->read(null, 1));
+
+		$this->assertTrue($this->Dbo->begin());
+		$this->assertTrue($model->delete(1));
+		$this->assertEmpty($model->read(null, 1));
+		$this->assertTrue($this->Dbo->rollback());
+		$this->assertNotEmpty($model->read(null, 1));
+
+		$this->assertTrue($this->Dbo->begin());
+		$this->assertTrue($model->delete(1));
+		$this->assertEmpty($model->read(null, 1));
+		$this->assertTrue($this->Dbo->commit());
+		$this->assertEmpty($model->read(null, 1));
+
+		$this->assertTrue($this->Dbo->rollback());
+		$this->assertNotEmpty($model->read(null, 1));
+	}
+
 }

From ffe0a1849582253432fc8aea6d4ee4b39b583dc2 Mon Sep 17 00:00:00 2001
From: Juan Basso <jrbasso@gmail.com>
Date: Sun, 1 Apr 2012 00:07:39 -0400
Subject: [PATCH 05/10] ReflectionMethod::setAccessible() is not compatible
 with PHP 5.2, causing fatal error in CI. Assuming that the db servers support
 nested transaction.

---
 lib/Cake/Test/Case/Model/Datasource/Database/MysqlTest.php    | 4 ----
 lib/Cake/Test/Case/Model/Datasource/Database/PostgresTest.php | 4 ----
 lib/Cake/Test/Case/Model/Datasource/Database/SqliteTest.php   | 4 ----
 3 files changed, 12 deletions(-)

diff --git a/lib/Cake/Test/Case/Model/Datasource/Database/MysqlTest.php b/lib/Cake/Test/Case/Model/Datasource/Database/MysqlTest.php
index a91069a60..bb7bc4c67 100644
--- a/lib/Cake/Test/Case/Model/Datasource/Database/MysqlTest.php
+++ b/lib/Cake/Test/Case/Model/Datasource/Database/MysqlTest.php
@@ -3586,10 +3586,6 @@ class MysqlTest extends CakeTestCase {
  * @return void
  */
 	public function testNestedTransaction() {
-		$obj = new ReflectionMethod($this->Dbo, '_supportNestedTransaction');
-		$obj->setAccessible(true);
-		$this->skipIf($obj->invoke($this->Dbo) === false, 'The MySQL server do not support nested transaction');
-
 		$this->loadFixtures('Address');
 		$model = ClassRegistry::init('Address');
 		$model->hasOne = $model->hasMany = $model->belongsTo = $model->hasAndBelongsToMany = array();
diff --git a/lib/Cake/Test/Case/Model/Datasource/Database/PostgresTest.php b/lib/Cake/Test/Case/Model/Datasource/Database/PostgresTest.php
index 4a6b7897e..68e0c3280 100644
--- a/lib/Cake/Test/Case/Model/Datasource/Database/PostgresTest.php
+++ b/lib/Cake/Test/Case/Model/Datasource/Database/PostgresTest.php
@@ -915,10 +915,6 @@ class PostgresTest extends CakeTestCase {
  * @return void
  */
 	public function testNestedTransaction() {
-		$obj = new ReflectionMethod($this->Dbo, '_supportNestedTransaction');
-		$obj->setAccessible(true);
-		$this->skipIf($obj->invoke($this->Dbo) === false, 'The Postgres server do not support nested transaction');
-
 		$this->loadFixtures('Article');
 		$model = new Article();
 		$model->hasOne = $model->hasMany = $model->belongsTo = $model->hasAndBelongsToMany = array();
diff --git a/lib/Cake/Test/Case/Model/Datasource/Database/SqliteTest.php b/lib/Cake/Test/Case/Model/Datasource/Database/SqliteTest.php
index 1e4ed7e46..49f99756b 100644
--- a/lib/Cake/Test/Case/Model/Datasource/Database/SqliteTest.php
+++ b/lib/Cake/Test/Case/Model/Datasource/Database/SqliteTest.php
@@ -389,10 +389,6 @@ class SqliteTest extends CakeTestCase {
  * @return void
  */
 	public function testNestedTransaction() {
-		$obj = new ReflectionMethod($this->Dbo, '_supportNestedTransaction');
-		$obj->setAccessible(true);
-		$this->skipIf($obj->invoke($this->Dbo) === false, 'The Sqlite version do not support nested transaction');
-
 		$this->loadFixtures('User');
 		$model = new User();
 		$model->hasOne = $model->hasMany = $model->belongsTo = $model->hasAndBelongsToMany = array();

From a512d466795380600a0223088f6b0d10605b936c Mon Sep 17 00:00:00 2001
From: Juan Basso <jrbasso@gmail.com>
Date: Sun, 1 Apr 2012 00:21:12 -0400
Subject: [PATCH 06/10] Sqlite is failing in PHP 5.2, re-adding the check for
 driver support.

---
 lib/Cake/Model/Datasource/Database/Mysql.php              | 2 +-
 lib/Cake/Model/Datasource/Database/Postgres.php           | 2 +-
 lib/Cake/Model/Datasource/Database/Sqlite.php             | 2 +-
 lib/Cake/Model/Datasource/DboSource.php                   | 8 ++++----
 .../Test/Case/Model/Datasource/Database/MysqlTest.php     | 2 ++
 .../Test/Case/Model/Datasource/Database/PostgresTest.php  | 2 ++
 .../Test/Case/Model/Datasource/Database/SqliteTest.php    | 2 ++
 7 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/lib/Cake/Model/Datasource/Database/Mysql.php b/lib/Cake/Model/Datasource/Database/Mysql.php
index ad618429a..b94ece767 100644
--- a/lib/Cake/Model/Datasource/Database/Mysql.php
+++ b/lib/Cake/Model/Datasource/Database/Mysql.php
@@ -681,7 +681,7 @@ class Mysql extends DboSource {
  *
  * @return boolean
  */
-	protected function _supportNestedTransaction() {
+	public function supportNestedTransaction() {
 		return version_compare($this->getVersion(), '4.1', '>=');
 	}
 
diff --git a/lib/Cake/Model/Datasource/Database/Postgres.php b/lib/Cake/Model/Datasource/Database/Postgres.php
index d681c8a64..261a06d6c 100644
--- a/lib/Cake/Model/Datasource/Database/Postgres.php
+++ b/lib/Cake/Model/Datasource/Database/Postgres.php
@@ -900,7 +900,7 @@ class Postgres extends DboSource {
  *
  * @return boolean
  */
-	protected function _supportNestedTransaction() {
+	public function supportNestedTransaction() {
 		return version_compare($this->getVersion(), '8.0', '>=');
 	}
 
diff --git a/lib/Cake/Model/Datasource/Database/Sqlite.php b/lib/Cake/Model/Datasource/Database/Sqlite.php
index 3eee31a54..cbc2caeaa 100644
--- a/lib/Cake/Model/Datasource/Database/Sqlite.php
+++ b/lib/Cake/Model/Datasource/Database/Sqlite.php
@@ -564,7 +564,7 @@ class Sqlite extends DboSource {
  *
  * @return boolean
  */
-	protected function _supportNestedTransaction() {
+	public function supportNestedTransaction() {
 		return version_compare($this->getVersion(), '3.6.8', '>=');
 	}
 
diff --git a/lib/Cake/Model/Datasource/DboSource.php b/lib/Cake/Model/Datasource/DboSource.php
index 47a6c2fd6..6c7f37a47 100644
--- a/lib/Cake/Model/Datasource/DboSource.php
+++ b/lib/Cake/Model/Datasource/DboSource.php
@@ -2022,7 +2022,7 @@ class DboSource extends DataSource {
  *
  * @return boolean
  */
-	protected function _supportNestedTransaction() {
+	public function supportNestedTransaction() {
 		return false;
 	}
 
@@ -2035,7 +2035,7 @@ class DboSource extends DataSource {
  */
 	public function begin() {
 		if ($this->_transactionStarted) {
-			if ($this->_supportNestedTransaction()) {
+			if ($this->supportNestedTransaction()) {
 				return $this->_beginNested();
 			}
 			$this->_transactionNesting++;
@@ -2083,7 +2083,7 @@ class DboSource extends DataSource {
 			return $this->_connection->commit();
 		}
 
-		if ($this->_supportNestedTransaction()) {
+		if ($this->supportNestedTransaction()) {
 			return $this->_commitNested();
 		}
 
@@ -2125,7 +2125,7 @@ class DboSource extends DataSource {
 			return $this->_connection->rollBack();
 		}
 
-		if ($this->_supportNestedTransaction()) {
+		if ($this->supportNestedTransaction()) {
 			return $this->_rollbackNested();
 		}
 
diff --git a/lib/Cake/Test/Case/Model/Datasource/Database/MysqlTest.php b/lib/Cake/Test/Case/Model/Datasource/Database/MysqlTest.php
index bb7bc4c67..9fa5f9bd4 100644
--- a/lib/Cake/Test/Case/Model/Datasource/Database/MysqlTest.php
+++ b/lib/Cake/Test/Case/Model/Datasource/Database/MysqlTest.php
@@ -3586,6 +3586,8 @@ class MysqlTest extends CakeTestCase {
  * @return void
  */
 	public function testNestedTransaction() {
+		$this->skipIf($this->Dbo->supportNestedTransaction() === false, 'The MySQL server do not support nested transaction');
+
 		$this->loadFixtures('Address');
 		$model = ClassRegistry::init('Address');
 		$model->hasOne = $model->hasMany = $model->belongsTo = $model->hasAndBelongsToMany = array();
diff --git a/lib/Cake/Test/Case/Model/Datasource/Database/PostgresTest.php b/lib/Cake/Test/Case/Model/Datasource/Database/PostgresTest.php
index 68e0c3280..eb249e4d3 100644
--- a/lib/Cake/Test/Case/Model/Datasource/Database/PostgresTest.php
+++ b/lib/Cake/Test/Case/Model/Datasource/Database/PostgresTest.php
@@ -915,6 +915,8 @@ class PostgresTest extends CakeTestCase {
  * @return void
  */
 	public function testNestedTransaction() {
+		$this->skipIf($this->Dbo->supportNestedTransaction() === false, 'The Postgres server do not support nested transaction');
+
 		$this->loadFixtures('Article');
 		$model = new Article();
 		$model->hasOne = $model->hasMany = $model->belongsTo = $model->hasAndBelongsToMany = array();
diff --git a/lib/Cake/Test/Case/Model/Datasource/Database/SqliteTest.php b/lib/Cake/Test/Case/Model/Datasource/Database/SqliteTest.php
index 49f99756b..a5a82cae1 100644
--- a/lib/Cake/Test/Case/Model/Datasource/Database/SqliteTest.php
+++ b/lib/Cake/Test/Case/Model/Datasource/Database/SqliteTest.php
@@ -389,6 +389,8 @@ class SqliteTest extends CakeTestCase {
  * @return void
  */
 	public function testNestedTransaction() {
+		$this->skipIf($this->Dbo->supportNestedTransaction() === false, 'The Sqlite version do not support nested transaction');
+
 		$this->loadFixtures('User');
 		$model = new User();
 		$model->hasOne = $model->hasMany = $model->belongsTo = $model->hasAndBelongsToMany = array();

From 79f7ca7d33c0efb828604954fbc820418036f3dc Mon Sep 17 00:00:00 2001
From: Juan Basso <jrbasso@gmail.com>
Date: Sun, 1 Apr 2012 00:25:10 -0400
Subject: [PATCH 07/10] Oops, forgot one change in last commit.

---
 lib/Cake/Test/Case/Model/Datasource/DboSourceTest.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/Cake/Test/Case/Model/Datasource/DboSourceTest.php b/lib/Cake/Test/Case/Model/Datasource/DboSourceTest.php
index 61d37b6bf..fffdb9f4c 100644
--- a/lib/Cake/Test/Case/Model/Datasource/DboSourceTest.php
+++ b/lib/Cake/Test/Case/Model/Datasource/DboSourceTest.php
@@ -51,7 +51,7 @@ class DboTestSource extends DboSource {
 		$this->_connection = $conn;
 	}
 
-	protected function _supportNestedTransaction() {
+	public function supportNestedTransaction() {
 		return true;
 	}
 

From b0a3a1a5aa6b86fe449b41bdf4a23ac37e69a139 Mon Sep 17 00:00:00 2001
From: Juan Basso <jrbasso@gmail.com>
Date: Sun, 1 Apr 2012 00:41:16 -0400
Subject: [PATCH 08/10] Added test to check when driver do not support nested
 support.

---
 .../Case/Model/Datasource/DboSourceTest.php   | 28 ++++++++++++++++++-
 1 file changed, 27 insertions(+), 1 deletion(-)

diff --git a/lib/Cake/Test/Case/Model/Datasource/DboSourceTest.php b/lib/Cake/Test/Case/Model/Datasource/DboSourceTest.php
index fffdb9f4c..5a2cd8549 100644
--- a/lib/Cake/Test/Case/Model/Datasource/DboSourceTest.php
+++ b/lib/Cake/Test/Case/Model/Datasource/DboSourceTest.php
@@ -35,6 +35,8 @@ class MockDataSource extends DataSource {
 
 class DboTestSource extends DboSource {
 
+	public static $nested = true;
+
 	public function connect($config = array()) {
 		$this->connected = true;
 	}
@@ -52,7 +54,7 @@ class DboTestSource extends DboSource {
 	}
 
 	public function supportNestedTransaction() {
-		return true;
+		return self::$nested;
 	}
 
 }
@@ -854,6 +856,7 @@ class DboSourceTest extends CakeTestCase {
 		$conn = $this->getMock('MockPDO');
 		$db = new DboTestSource();
 		$db->setConnection($conn);
+		DboTestSource::$nested = true;
 
 		$conn->expects($this->at(0))->method('beginTransaction')->will($this->returnValue(true));
 		$conn->expects($this->at(1))->method('exec')->with($this->equalTo('SAVEPOINT LEVEL1'))->will($this->returnValue(true));
@@ -870,6 +873,29 @@ class DboSourceTest extends CakeTestCase {
 		$db->commit();
 	}
 
+/**
+ * Test nested transaction calls without support
+ *
+ * @return void
+ */
+	public function testTransactionNestedWithoutSupport() {
+		$conn = $this->getMock('MockPDO');
+		$db = new DboTestSource();
+		$db->setConnection($conn);
+		DboTestSource::$nested = false;
+
+		$conn->expects($this->once())->method('beginTransaction')->will($this->returnValue(true));
+		$conn->expects($this->never())->method('exec');
+		$conn->expects($this->once())->method('commit')->will($this->returnValue(true));
+
+		$db->begin();
+		$db->begin();
+		$db->commit();
+		$db->begin();
+		$db->rollback();
+		$db->commit();
+	}
+
 /**
  * Test build statement with some fields missing
  *

From 7be5349b0cf47c03b39a455a2d3cd9a4404777ff Mon Sep 17 00:00:00 2001
From: Juan Basso <jrbasso@gmail.com>
Date: Sat, 14 Apr 2012 16:41:08 -0400
Subject: [PATCH 09/10] Added configuration to disable nested transaction, even
 if the db supports it.

---
 lib/Cake/Model/Datasource/Database/Mysql.php  |  2 +-
 .../Model/Datasource/Database/Postgres.php    |  2 +-
 lib/Cake/Model/Datasource/Database/Sqlite.php |  2 +-
 lib/Cake/Model/Datasource/DboSource.php       |  9 +++++++
 .../Case/Model/Datasource/DboSourceTest.php   | 26 ++++++++++++++++++-
 5 files changed, 37 insertions(+), 4 deletions(-)

diff --git a/lib/Cake/Model/Datasource/Database/Mysql.php b/lib/Cake/Model/Datasource/Database/Mysql.php
index b94ece767..70c51366c 100644
--- a/lib/Cake/Model/Datasource/Database/Mysql.php
+++ b/lib/Cake/Model/Datasource/Database/Mysql.php
@@ -682,7 +682,7 @@ class Mysql extends DboSource {
  * @return boolean
  */
 	public function supportNestedTransaction() {
-		return version_compare($this->getVersion(), '4.1', '>=');
+		return $this->nestedTransaction && version_compare($this->getVersion(), '4.1', '>=');
 	}
 
 }
diff --git a/lib/Cake/Model/Datasource/Database/Postgres.php b/lib/Cake/Model/Datasource/Database/Postgres.php
index 261a06d6c..35f568aad 100644
--- a/lib/Cake/Model/Datasource/Database/Postgres.php
+++ b/lib/Cake/Model/Datasource/Database/Postgres.php
@@ -901,7 +901,7 @@ class Postgres extends DboSource {
  * @return boolean
  */
 	public function supportNestedTransaction() {
-		return version_compare($this->getVersion(), '8.0', '>=');
+		return $this->nestedTransaction && version_compare($this->getVersion(), '8.0', '>=');
 	}
 
 }
diff --git a/lib/Cake/Model/Datasource/Database/Sqlite.php b/lib/Cake/Model/Datasource/Database/Sqlite.php
index cbc2caeaa..419709892 100644
--- a/lib/Cake/Model/Datasource/Database/Sqlite.php
+++ b/lib/Cake/Model/Datasource/Database/Sqlite.php
@@ -565,7 +565,7 @@ class Sqlite extends DboSource {
  * @return boolean
  */
 	public function supportNestedTransaction() {
-		return version_compare($this->getVersion(), '3.6.8', '>=');
+		return $this->nestedTransaction && version_compare($this->getVersion(), '3.6.8', '>=');
 	}
 
 }
diff --git a/lib/Cake/Model/Datasource/DboSource.php b/lib/Cake/Model/Datasource/DboSource.php
index 6c7f37a47..a37709df9 100644
--- a/lib/Cake/Model/Datasource/DboSource.php
+++ b/lib/Cake/Model/Datasource/DboSource.php
@@ -69,6 +69,15 @@ class DboSource extends DataSource {
  */
 	public $cacheMethods = true;
 
+/**
+ * Flag to support nested transactions. If it is set to false, you will be able to use
+ * the transaction methods (begin/commit/rollback), but just the global transaction will
+ * be executed.
+ *
+ * @var boolean
+ */
+	public $nestedTransaction = true;
+
 /**
  * Print full query debug info?
  *
diff --git a/lib/Cake/Test/Case/Model/Datasource/DboSourceTest.php b/lib/Cake/Test/Case/Model/Datasource/DboSourceTest.php
index 5a2cd8549..647c373c4 100644
--- a/lib/Cake/Test/Case/Model/Datasource/DboSourceTest.php
+++ b/lib/Cake/Test/Case/Model/Datasource/DboSourceTest.php
@@ -54,7 +54,7 @@ class DboTestSource extends DboSource {
 	}
 
 	public function supportNestedTransaction() {
-		return self::$nested;
+		return $this->nestedTransaction && self::$nested;
 	}
 
 }
@@ -879,6 +879,30 @@ class DboSourceTest extends CakeTestCase {
  * @return void
  */
 	public function testTransactionNestedWithoutSupport() {
+		$conn = $this->getMock('MockPDO');
+		$db = new DboTestSource();
+		$db->setConnection($conn);
+		$db->nestedTransaction = false;
+		DboTestSource::$nested = true;
+
+		$conn->expects($this->once())->method('beginTransaction')->will($this->returnValue(true));
+		$conn->expects($this->never())->method('exec');
+		$conn->expects($this->once())->method('commit')->will($this->returnValue(true));
+
+		$db->begin();
+		$db->begin();
+		$db->commit();
+		$db->begin();
+		$db->rollback();
+		$db->commit();
+	}
+
+/**
+ * Test nested transaction disabled
+ *
+ * @return void
+ */
+	public function testTransactionNestedDisabled() {
 		$conn = $this->getMock('MockPDO');
 		$db = new DboTestSource();
 		$db->setConnection($conn);

From 37157806b920eddcc68bef63fad12d904942ce76 Mon Sep 17 00:00:00 2001
From: Juan Basso <jrbasso@gmail.com>
Date: Sat, 14 Apr 2012 16:46:47 -0400
Subject: [PATCH 10/10] Removing some dup code in nested transaction tests.

---
 .../Case/Model/Datasource/DboSourceTest.php   | 24 +++++++++----------
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/lib/Cake/Test/Case/Model/Datasource/DboSourceTest.php b/lib/Cake/Test/Case/Model/Datasource/DboSourceTest.php
index 647c373c4..7824a7ef2 100644
--- a/lib/Cake/Test/Case/Model/Datasource/DboSourceTest.php
+++ b/lib/Cake/Test/Case/Model/Datasource/DboSourceTest.php
@@ -865,12 +865,7 @@ class DboSourceTest extends CakeTestCase {
 		$conn->expects($this->at(4))->method('exec')->with($this->equalTo('ROLLBACK TO SAVEPOINT LEVEL1'))->will($this->returnValue(true));
 		$conn->expects($this->at(5))->method('commit')->will($this->returnValue(true));
 
-		$db->begin();
-		$db->begin();
-		$db->commit();
-		$db->begin();
-		$db->rollback();
-		$db->commit();
+		$this->_runTransactions($db);
 	}
 
 /**
@@ -889,12 +884,7 @@ class DboSourceTest extends CakeTestCase {
 		$conn->expects($this->never())->method('exec');
 		$conn->expects($this->once())->method('commit')->will($this->returnValue(true));
 
-		$db->begin();
-		$db->begin();
-		$db->commit();
-		$db->begin();
-		$db->rollback();
-		$db->commit();
+		$this->_runTransactions($db);
 	}
 
 /**
@@ -912,6 +902,16 @@ class DboSourceTest extends CakeTestCase {
 		$conn->expects($this->never())->method('exec');
 		$conn->expects($this->once())->method('commit')->will($this->returnValue(true));
 
+		$this->_runTransactions($db);
+	}
+
+/**
+ * Nested transaction calls
+ *
+ * @param DboTestSource $db
+ * @return void
+ */
+	protected function _runTransactions($db) {
 		$db->begin();
 		$db->begin();
 		$db->commit();