当我尝试启动 MySQL 时，我得到：
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2)
当我使用 sudo 时，我得到：
Starting MySQL
. ERROR! The server quit without updating PID file (/usr/local/var/mysql/Victorias-MacBook-Pro.local.pid).
我正在使用 Mac OS X 10.7。我通过自制软件安装了 MySQL，并安装了 MySQL 5.5.20。
这是我得到的 .err 文件：
120513 22:30:03 mysqld_safe Starting mysqld daemon with databases from /usr/local/var/mysql
120513 22:30:03 [Warning] Setting lower_case_table_names=2 because file system for /usr/local/var/mysql/ is case insensitive
/usr/local/Cellar/mysql/5.5.20/bin/mysqld: Table 'mysql.plugin' doesn't exist
120513 22:30:03 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.
120513 22:30:03 InnoDB: The InnoDB memory heap is disabled
120513 22:30:03 InnoDB: Mutexes and rw_locks use GCC atomic builtins
120513 22:30:03 InnoDB: Compressed tables use zlib 1.2.5
120513 22:30:03 InnoDB: Initializing buffer pool, size = 128.0M
120513 22:30:03 InnoDB: Completed initialization of buffer pool
120513 22:30:03 InnoDB: highest supported file format is Barracuda.
120513 22:30:03 InnoDB: Waiting for the background threads to start
120513 22:30:04 InnoDB: 1.1.8 started; log sequence number 1595675
120513 22:30:04 [ERROR] Fatal error: Can't open and lock privilege tables: Table 'mysql.host' doesn't exist
120513 22:30:04 mysqld_safe mysqld from pid file /usr/local/var/mysql/Victorias-MacBook-Pro.local.pid ended
120513 22:30:13 mysqld_safe Starting mysqld daemon with databases from /usr/local/var/mysql
120513 22:30:13 [Warning] Setting lower_case_table_names=2 because file system for /usr/local/var/mysql/ is case insensitive
/usr/local/Cellar/mysql/5.5.20/bin/mysqld: Table 'mysql.plugin' doesn't exist
120513 22:30:13 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.
120513 22:30:13 InnoDB: The InnoDB memory heap is disabled
120513 22:30:13 InnoDB: Mutexes and rw_locks use GCC atomic builtins
120513 22:30:13 InnoDB: Compressed tables use zlib 1.2.5
120513 22:30:13 InnoDB: Initializing buffer pool, size = 128.0M
120513 22:30:13 InnoDB: Completed initialization of buffer pool
120513 22:30:13 InnoDB: highest supported file format is Barracuda.
120513 22:30:13 InnoDB: Waiting for the background threads to start
120513 22:30:14 InnoDB: 1.1.8 started; log sequence number 1595675
120513 22:30:14 [ERROR] Fatal error: Can't open and lock privilege tables: Table 'mysql.host' doesn't exist
120513 22:30:14 mysqld_safe mysqld from pid file /usr/local/var/mysql/Victorias-MacBook-Pro.local.pid ended
120513 22:30:24 mysqld_safe Starting mysqld daemon with databases from /usr/local/var/mysql
120513 22:30:24 [Warning] Setting lower_case_table_names=2 because file system for /usr/local/var/mysql/ is case insensitive
/usr/local/Cellar/mysql/5.5.20/bin/mysqld: Table 'mysql.plugin' doesn't exist
120513 22:30:24 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.
120513 22:30:24 InnoDB: The InnoDB memory heap is disabled
120513 22:30:24 InnoDB: Mutexes and rw_locks use GCC atomic builtins
120513 22:30:24 InnoDB: Compressed tables use zlib 1.2.5
120513 22:30:24 InnoDB: Initializing buffer pool, size = 128.0M
120513 22:30:24 InnoDB: Completed initialization of buffer pool
120513 22:30:24 InnoDB: highest supported file format is Barracuda.
120513 22:30:24 InnoDB: Waiting for the background threads to start
120513 22:30:25 InnoDB: 1.1.8 started; log sequence number 1595675
120513 22:30:25 [ERROR] Fatal error: Can't open and lock privilege tables: Table 'mysql.host' doesn't exist
120513 22:30:25 mysqld_safe mysqld from pid file /usr/local/var/mysql/Victorias-MacBook-Pro.local.pid ended
120513 22:30:34 mysqld_safe Starting mysqld daemon with databases from /usr/local/var/mysql
120513 22:30:34 [Warning] Setting lower_case_table_names=2 because file system for /usr/local/var/mysql/ is case insensitive
/usr/local/Cellar/mysql/5.5.20/bin/mysqld: Table 'mysql.plugin' doesn't exist
120513 22:30:34 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.
120513 22:30:34 InnoDB: The InnoDB memory heap is disabled
120513 22:30:34 InnoDB: Mutexes and rw_locks use GCC atomic builtins
120513 22:30:34 InnoDB: Compressed tables use zlib 1.2.5
120513 22:30:34 InnoDB: Initializing buffer pool, size = 128.0M
120513 22:30:34 InnoDB: Completed initialization of buffer pool
120513 22:30:34 InnoDB: highest supported file format is Barracuda.
120513 22:30:34 InnoDB: Waiting for the background threads to start
120513 22:30:35 InnoDB: 1.1.8 started; log sequence number 1595675
120513 22:30:35 [ERROR] Fatal error: Can't open and lock privilege tables: Table 'mysql.host' doesn't exist
120513 22:30:35 mysqld_safe mysqld from pid file /usr/local/var/mysql/Victorias-MacBook-Pro.local.pid ended
120513 22:30:44 mysqld_safe Starting mysqld daemon with databases from /usr/local/var/mysql
120513 22:30:44 [Warning] Setting lower_case_table_names=2 because file system for /usr/local/var/mysql/ is case insensitive
/usr/local/Cellar/mysql/5.5.20/bin/mysqld: Table 'mysql.plugin' doesn't exist
120513 22:30:44 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.
120513 22:30:44 InnoDB: The InnoDB memory heap is disabled
120513 22:30:44 InnoDB: Mutexes and rw_locks use GCC atomic builtins
120513 22:30:44 InnoDB: Compressed tables use zlib 1.2.5
120513 22:30:44 InnoDB: Initializing buffer pool, size = 128.0M
120513 22:30:44 InnoDB: Completed initialization of buffer pool
120513 22:30:44 InnoDB: highest supported file format is Barracuda.
120513 22:30:44 InnoDB: Waiting for the background threads to start
120513 22:30:45 InnoDB: 1.1.8 started; log sequence number 1595675
120513 22:30:45 [ERROR] Fatal error: Can't open and lock privilege tables: Table 'mysql.host' doesn't exist
120513 22:30:45 mysqld_safe mysqld from pid file /usr/local/var/mysql/Victorias-MacBook-Pro.local.pid ended
120513 22:30:54 mysqld_safe Starting mysqld daemon with databases from /usr/local/var/mysql
120513 22:30:54 [Warning] Setting lower_case_table_names=2 because file system for /usr/local/var/mysql/ is case insensitive
/usr/local/Cellar/mysql/5.5.20/bin/mysqld: Table 'mysql.plugin' doesn't exist
120513 22:30:54 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.
120513 22:30:54 InnoDB: The InnoDB memory heap is disabled
120513 22:30:54 InnoDB: Mutexes and rw_locks use GCC atomic builtins
120513 22:30:54 InnoDB: Compressed tables use zlib 1.2.5
120513 22:30:54 InnoDB: Initializing buffer pool, size = 128.0M
120513 22:30:54 InnoDB: Completed initialization of buffer pool
120513 22:30:54 InnoDB: highest supported file format is Barracuda.
120513 22:30:54 InnoDB: Waiting for the background threads to start
120513 22:30:55 InnoDB: 1.1.8 started; log sequence number 1595675
120513 22:30:55 [ERROR] Fatal error: Can't open and lock privilege tables: Table 'mysql.host' doesn't exist
120513 22:30:55 mysqld_safe mysqld from pid file /usr/local/var/mysql/Victorias-MacBook-Pro.local.pid ended
120513 22:31:04 mysqld_safe Starting mysqld daemon with databases from /usr/local/var/mysql
120513 22:31:04 [Warning] Setting lower_case_table_names=2 because file system for /usr/local/var/mysql/ is case insensitive
/usr/local/Cellar/mysql/5.5.20/bin/mysqld: Table 'mysql.plugin' doesn't exist
120513 22:31:04 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.
120513 22:31:04 InnoDB: The InnoDB memory heap is disabled
120513 22:31:04 InnoDB: Mutexes and rw_locks use GCC atomic builtins
120513 22:31:04 InnoDB: Compressed tables use zlib 1.2.5
120513 22:31:04 InnoDB: Initializing buffer pool, size = 128.0M
120513 22:31:04 InnoDB: Completed initialization of buffer pool
120513 22:31:04 InnoDB: highest supported file format is Barracuda.
120513 22:31:04 InnoDB: Waiting for the background threads to start