feat(Cmake/Database): separate database lib from common (#5334)

* feat(Core/Database): separate databse lib from common

* 1

src/server/database/Database/MySQLThreading.h

@@ -0,0 +1,47 @@
+/*
+ * Copyright (C) 2016+     AzerothCore <www.azerothcore.org>
+ * Copyright (C) 2008-2016 TrinityCore <http://www.trinitycore.org/>
+ * Copyright (C) 2005-2009 MaNGOS <http://getmangos.com/>
+ */
+
+#ifndef _MYSQLTHREADING_H
+#define _MYSQLTHREADING_H
+
+#include "Log.h"
+
+class MySQL
+{
+public:
+    /*! Create a thread on the MySQL server to mirrior the calling thread,
+        initializes thread-specific variables and allows thread-specific
+        operations without concurrence from other threads.
+        This should only be called if multiple core threads are running
+        on the same MySQL connection. Seperate MySQL connections implicitly
+        create a mirror thread.
+    */
+    static void Thread_Init()
+    {
+        mysql_thread_init();
+    }
+
+    /*! Shuts down MySQL thread and frees resources, should only be called
+        when we terminate. MySQL threads and connections are not configurable
+        during runtime.
+    */
+    static void Thread_End()
+    {
+        mysql_thread_end();
+    }
+
+    static void Library_Init()
+    {
+        mysql_library_init(-1, nullptr, nullptr);
+    }
+
+    static void Library_End()
+    {
+        mysql_library_end();
+    }
+};
+
+#endif