最后更新：我忘記了運行initdb命令。</最終更新>通過運行此命令ps auxwww | grep postgres我看到postgres沒有運行> ps auxwww | grep postgresremcat          1789   0.0  0.0  2434892    480 s000  R+   11:28PM   0:00.00 grep postgres這提出了一個問題：如何啟動postgresql服務器？更新：>pg_ctl -D /usr/local/var/postgres -l /usr/local/var/postgres/server.log startserver startingsh: /usr/local/var/postgres/server.log: No such file or directory更新2：觸摸不成功，所以我改為這樣做：> mkdir /usr/local/var/postgres> vi /usr/local/var/postgres/server.log> ls /usr/local/var/postgres/          server.log但是，當我嘗試啟動Rails服務器時，仍然看到以下內容：Is the server running on host "localhost" and acceptingTCP/IP connections on port 5432?更新3：> pg_ctl -D /usr/local/var/postgres statuspg_ctl: no server running更新4：我發現那里沒有pg_hba.conf（只有pg_hba.conf.sample），所以我修改了示例并將其重命名（以刪除.sample）。這里是內容： # IPv4 local connections: host    all             all             127.0.0.1/32           trust # IPv6 local connections: host    all             all             ::1/128                trust但我不明白這一點：> pg_ctl -D /usr/local/var/postgres -l /usr/local/var/postgres/server.log start     server starting> pg_ctl -D /usr/local/var/postgres status                                     pg_ctl: no server running也：sudo find / -name postgresql.conffind: /dev/fd/3: Not a directoryfind: /dev/fd/4: Not a directory更新5：sudo pg_ctl -D /usr/local/var/postgres -l /usr/local/var/postgres/server.log startPassword:pg_ctl: cannot be run as rootPlease log in (using, e.g., "su") as the (unprivileged) user that will own the server process.更新6：這似乎很奇怪：> egrep 'listen|port' /usr/local/var/postgres/postgresql.confegrep: /usr/local/var/postgres/postgresql.conf: No such file or directory不過，我確實這樣做：>sudo find / -name "*postgresql.conf*"find: /dev/fd/3: Not a directoryfind: /dev/fd/4: Not a directory/usr/local/Cellar/postgresql/9.0.4/share/postgresql/postgresql.conf.sample/usr/share/postgresql/postgresql.conf.sampl