diff --git a/extensions/sphinx/Schema.php b/extensions/sphinx/Schema.php
index ad25da2..5d1fc4b 100644
--- a/extensions/sphinx/Schema.php
+++ b/extensions/sphinx/Schema.php
@@ -518,4 +518,15 @@ class Schema extends Object
             throw new Exception($message, $errorInfo, (int) $e->getCode(), $e);
         }
     }
+
+    /**
+     * Returns a value indicating whether a SQL statement is for read purpose.
+     * @param string $sql the SQL statement
+     * @return boolean whether a SQL statement is for read purpose.
+     */
+    public function isReadQuery($sql)
+    {
+        $pattern = '/^\s*(SELECT|SHOW|DESCRIBE)\b/i';
+        return preg_match($pattern, $sql) > 0;
+    }
 }
diff --git a/framework/db/Schema.php b/framework/db/Schema.php
index fccca8f..5f36c14 100644
--- a/framework/db/Schema.php
+++ b/framework/db/Schema.php
@@ -520,9 +520,14 @@ abstract class Schema extends Object
         }
     }
 
+    /**
+     * Returns a value indicating whether a SQL statement is for read purpose.
+     * @param string $sql the SQL statement
+     * @return boolean whether a SQL statement is for read purpose.
+     */
     public function isReadQuery($sql)
     {
         $pattern = '/^\s*(SELECT|SHOW|DESCRIBE)\b/i';
-        return preg_match($pattern, $sql);
+        return preg_match($pattern, $sql) > 0;
     }
 }