From a1aa73c1a2893469b7f8399d21b86f962a914498 Mon Sep 17 00:00:00 2001
From: ADmad <admad.coder@gmail.com>
Date: Sun, 7 Oct 2012 20:17:31 +0530
Subject: [PATCH] Cache character set names

---
 lib/Cake/Model/Datasource/Database/Mysql.php  | 33 ++++++++++++++-----
 .../Model/Datasource/Database/MysqlTest.php   | 30 ++++++++++++++++-
 2 files changed, 54 insertions(+), 9 deletions(-)

diff --git a/lib/Cake/Model/Datasource/Database/Mysql.php b/lib/Cake/Model/Datasource/Database/Mysql.php
index dff20613b..aa00f9d2c 100644
--- a/lib/Cake/Model/Datasource/Database/Mysql.php
+++ b/lib/Cake/Model/Datasource/Database/Mysql.php
@@ -119,6 +119,13 @@ class Mysql extends DboSource {
 		'boolean' => array('name' => 'tinyint', 'limit' => '1')
 	);
 
+/**
+ * Mapping of collation names to character set names
+ *
+ * @var array
+ */
+	protected $_charsets = array();
+
 /**
  * Connects to the database using options in the given configuration array.
  *
@@ -156,6 +163,7 @@ class Mysql extends DboSource {
 			));
 		}
 
+		$this->_charsets = array();
 		$this->_useAlias = (bool)version_compare($this->getVersion(), "4.1", ">=");
 
 		return $this->connected;
@@ -262,15 +270,24 @@ class Mysql extends DboSource {
  * @return string Character set name
  */
 	public function getCharsetName($name) {
-		if ((bool)version_compare($this->getVersion(), "5", ">=")) {
-			$r = $this->_execute('SELECT CHARACTER_SET_NAME FROM INFORMATION_SCHEMA.COLLATIONS WHERE COLLATION_NAME = ?', array($name));
-			$cols = $r->fetch(PDO::FETCH_ASSOC);
-
-			if (isset($cols['CHARACTER_SET_NAME'])) {
-				return $cols['CHARACTER_SET_NAME'];
-			}
+		if ((bool)version_compare($this->getVersion(), "5", "<")) {
+			return false;
 		}
-		return false;
+		if (isset($this->_charsets[$name])) {
+			return $this->_charsets[$name];
+		}
+		$r = $this->_execute(
+			'SELECT CHARACTER_SET_NAME FROM INFORMATION_SCHEMA.COLLATIONS WHERE COLLATION_NAME = ?',
+			array($name)
+		);
+		$cols = $r->fetch(PDO::FETCH_ASSOC);
+
+		if (isset($cols['CHARACTER_SET_NAME'])) {
+			$this->_charsets[$name] = $cols['CHARACTER_SET_NAME'];
+		} else {
+			$this->_charsets[$name] = false;
+		}
+		return $this->_charsets[$name];
 	}
 
 /**
diff --git a/lib/Cake/Test/Case/Model/Datasource/Database/MysqlTest.php b/lib/Cake/Test/Case/Model/Datasource/Database/MysqlTest.php
index caddc5b7a..a738a9528 100644
--- a/lib/Cake/Test/Case/Model/Datasource/Database/MysqlTest.php
+++ b/lib/Cake/Test/Case/Model/Datasource/Database/MysqlTest.php
@@ -773,7 +773,7 @@ class MysqlTest extends CakeTestCase {
 	}
 
 /**
- * testBuildTableParameters method
+ * testGetCharsetName method
  *
  * @return void
  */
@@ -785,6 +785,34 @@ class MysqlTest extends CakeTestCase {
 		$this->assertEquals('cp1250', $result);
 	}
 
+/**
+ * testGetCharsetNameCaching method
+ *
+ * @return void
+ */
+	public function testGetCharsetNameCaching() {
+		$db = $this->getMock('Mysql', array('connect', '_execute', 'getVersion'));
+		$queryResult = $this->getMock('PDOStatement');
+
+		$db->expects($this->exactly(2))->method('getVersion')->will($this->returnValue('5.1'));
+
+		$db->expects($this->exactly(1))
+			->method('_execute')
+			->with('SELECT CHARACTER_SET_NAME FROM INFORMATION_SCHEMA.COLLATIONS WHERE COLLATION_NAME = ?', array('utf8_unicode_ci'))
+			->will($this->returnValue($queryResult));
+
+		$queryResult->expects($this->once())
+			->method('fetch')
+			->with(PDO::FETCH_ASSOC)
+			->will($this->returnValue(array('CHARACTER_SET_NAME' => 'utf8')));
+
+		$result = $db->getCharsetName('utf8_unicode_ci');
+		$this->assertEquals('utf8', $result);
+
+		$result = $db->getCharsetName('utf8_unicode_ci');
+		$this->assertEquals('utf8', $result);
+	}
+
 /**
  * test that changing the virtualFieldSeparator allows for __ fields.
  *