From b638cc4a4e241146e151be4afaeb1ad2eb6766ef Mon Sep 17 00:00:00 2001
From: Brandon Kelly <brandon@pixelandtonic.com>
Date: Sat, 8 Jun 2019 12:48:35 -0700
Subject: [PATCH] Fixes #17348: Improved performance of
 `yii\db\Connection::quoteTableName()`

---
 framework/CHANGELOG.md      | 1 +
 framework/db/Connection.php | 9 ++++++++-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/framework/CHANGELOG.md b/framework/CHANGELOG.md
index bcdffbc..99cdb9c 100644
--- a/framework/CHANGELOG.md
+++ b/framework/CHANGELOG.md
@@ -6,6 +6,7 @@ Yii Framework 2 Change Log
 
 - Bug #17341: Fixed error from yii.activeForm.js in strict mode (mikehaertl)
 - Enh #17345: Improved performance of `yii\db\Connection::quoteColumnName()` (brandonkelly)
+- Enh #17348: Improved performance of `yii\db\Connection::quoteTableName()` (brandonkelly)
 
 
 2.0.20 June 04, 2019
diff --git a/framework/db/Connection.php b/framework/db/Connection.php
index 1d50104..3feb085 100644
--- a/framework/db/Connection.php
+++ b/framework/db/Connection.php
@@ -442,6 +442,10 @@ class Connection extends Component
      */
     private $_queryCacheInfo = [];
     /**
+     * @var string[] quoted table name cache for [[quoteTableName()]] calls
+     */
+    private $_quotedTableNames;
+    /**
      * @var string[] quoted column name cache for [[quoteColumnName()]] calls
      */
     private $_quotedColumnNames;
@@ -895,7 +899,10 @@ class Connection extends Component
      */
     public function quoteTableName($name)
     {
-        return $this->getSchema()->quoteTableName($name);
+        if (isset($this->_quotedTableNames[$name])) {
+            return $this->_quotedTableNames[$name];
+        }
+        return $this->_quotedTableNames[$name] = $this->getSchema()->quoteTableName($name);
     }
 
     /**