错误在哪里出现？ 能否把 app/logs/下的日志贴出来。

[2013-11-15 15:56:52] request.CRITICAL: Uncaught PHP Exception PDOException: "SQLSTATE[HY000] [2002] No such file or directory" at /Applications/AMPPS/www/edusoho/app/cache/prod/appProdProjectContainer.php line 762 {"exception":"[object] (PDOException: SQLSTATE[HY000] [2002] No such file or directory at /Applications/AMPPS/www/edusoho/app/cache/prod/appProdProjectContainer.php:762)"} []
[2013-11-15 15:56:52] request.CRITICAL: Exception thrown when handling an exception (PDOException: SQLSTATE[HY000] [2002] No such file or directory) {"exception":"[object] (PDOException: SQLSTATE[HY000] [2002] No such file or directory at /Applications/AMPPS/www/edusoho/app/cache/prod/appProdProjectContainer.php:762)"} []
[2013-11-15 15:57:04] request.CRITICAL: Uncaught PHP Exception PDOException: "SQLSTATE[HY000] [2002] No such file or directory" at /Applications/AMPPS/www/edusoho/app/cache/prod/appProdProjectContainer.php line 762 {"exception":"[object] (PDOException: SQLSTATE[HY000] [2002] No such file or directory at /Applications/AMPPS/www/edusoho/app/cache/prod/appProdProjectContainer.php:762)"} []
[2013-11-15 15:57:04] request.CRITICAL: Exception thrown when handling an exception (PDOException: SQLSTATE[HY000] [2002] No such file or directory) {"exception":"[object] (PDOException: SQLSTATE[HY000] [2002] No such file or directory at /Applications/AMPPS/www/edusoho/app/cache/prod/appProdProjectContainer.php:762)"} []
[2013-11-15 15:57:10] request.CRITICAL: Uncaught PHP Exception PDOException: "SQLSTATE[HY000] [2002] No such file or directory" at /Applications/AMPPS/www/edusoho/app/cache/prod/appProdProjectContainer.php line 762 {"exception":"[object] (PDOException: SQLSTATE[HY000] [2002] No such file or directory at /Applications/AMPPS/www/edusoho/app/cache/prod/appProdProjectContainer.php:762)"} []
[2013-11-15 15:57:10] request.CRITICAL: Exception thrown when handling an exception (PDOException: SQLSTATE[HY000] [2002] No such file or directory) {"exception":"[object] (PDOException: SQLSTATE[HY000] [2002] No such file or directory at /Applications/AMPPS/www/edusoho/app/cache/prod/appProdProjectContainer.php:762)"} []
[2013-11-15 15:59:29] request.CRITICAL: Uncaught PHP Exception PDOException: "SQLSTATE[HY000] [2002] No such file or directory" at /Applications/AMPPS/www/edusoho/app/cache/prod/appProdProjectContainer.php line 762 {"exception":"[object] (PDOException: SQLSTATE[HY000] [2002] No such file or directory at /Applications/AMPPS/www/edusoho/app/cache/prod/appProdProjectContainer.php:762)"} []
[2013-11-15 15:59:29] request.CRITICAL: Exception thrown when handling an exception (PDOException: SQLSTATE[HY000] [2002] No such file or directory) {"exception":"[object] (PDOException: SQLSTATE[HY000] [2002] No such file or directory at /Applications/AMPPS/www/edusoho/app/cache/prod/appProdProjectContainer.php:762)"} []
[2013-11-15 16:02:22] request.CRITICAL: Uncaught PHP Exception PDOException: "SQLSTATE[HY000] [2002] No such file or directory" at /Applications/AMPPS/www/edusoho/app/cache/prod/appProdProjectContainer.php line 762 {"exception":"[object] (PDOException: SQLSTATE[HY000] [2002] No such file or directory at /Applications/AMPPS/www/edusoho/app/cache/prod/appProdProjectContainer.php:762)"} []
[2013-11-15 16:02:23] request.CRITICAL: Exception thrown when handling an exception (PDOException: SQLSTATE[HY000] [2002] No such file or directory) {"exception":"[object] (PDOException: SQLSTATE[HY000] [2002] No such file or directory at /Applications/AMPPS/www/edusoho/app/cache/prod/appProdProjectContainer.php:762)"} []
[2013-11-15 16:03:21] request.CRITICAL: Uncaught PHP Exception PDOException: "SQLSTATE[HY000] [2002] No such file or directory" at /Applications/AMPPS/www/edusoho/app/cache/prod/appProdProjectContainer.php line 762 {"exception":"[object] (PDOException: SQLSTATE[HY000] [2002] No such file or directory at /Applications/AMPPS/www/edusoho/app/cache/prod/appProdProjectContainer.php:762)"} []
[2013-11-15 16:03:21] request.CRITICAL: Exception thrown when handling an exception (PDOException: SQLSTATE[HY000] [2002] No such file or directory) {"exception":"[object] (PDOException: SQLSTATE[HY000] [2002] No such file or directory at /Applications/AMPPS/www/edusoho/app/cache/prod/appProdProjectContainer.php:762)"} []
[2013-11-15 16:15:41] request.CRITICAL: Uncaught PHP Exception PDOException: "SQLSTATE[HY000] [2002] No such file or directory" at /Applications/AMPPS/www/edusoho/app/cache/prod/appProdProjectContainer.php line 762 {"exception":"[object] (PDOException: SQLSTATE[HY000] [2002] No such file or directory at /Applications/AMPPS/www/edusoho/app/cache/prod/appProdProjectContainer.php:762)"} []
[2013-11-15 16:15:41] request.CRITICAL: Exception thrown when handling an exception (PDOException: SQLSTATE[HY000] [2002] No such file or directory) {"exception":"[object] (PDOException: SQLSTATE[HY000] [2002] No such file or directory at /Applications/AMPPS/www/edusoho/app/cache/prod/appProdProjectContainer.php:762)"} []

原因是： 

  链接数据库的 socket找不到。  

1、mysql启动会创建一个mysql.sock,这个文件会有一个路径

2、但是php却去另外一个路径找mysql.sock。  

解决方法：

1、给php.ini设置mysql.sock的路径

2、或者 php.ini指向的mysql.sock文件，你将他做个软链接指向mysql的mysql.sock

具体参考：http://forum.symfony-project.org/viewtopic.php?f=21&t=29653