Postgresql服务器正在本地运行，但psql无法连接。

在执行 brew install postgres 后：

brew install postgres
brew link --overwrite postgresql

Postgres 已经在运行：

/~ $brew services start postgresql
Service `postgresql` already started, use `brew services restart postgresql` to restart.

但是我们怎么使用 psql 客户端连接呢？

13:47:28/~ $psql
psql: could not connect to server: No such file or directory
    Is the server running locally and accepting
    connections on Unix domain socket "/tmp/.s.PGSQL.5432"?

更新 尝试了各种建议。

尝试重新启动..

 $brew services start postgresql
Service `postgresql` already started, use `brew services restart postgresql` to restart.
14:37:19/fastparquet $brew services restart postgresql
Stopping `postgresql`... (might take a while)
==> Successfully stopped `postgresql` (label: homebrew.mxcl.postgresql)
==> Successfully started `postgresql` (label: homebrew.mxcl.postgresql)
14:37:39/fastparquet $psql
psql: could not connect to server: No such file or directory
    Is the server running locally and accepting
    connections on Unix domain socket "/tmp/.s.PGSQL.5432"?
14:37:55/fastparquet $

连接到本地主机？

14:37:34/fastparquet $psql -h localhost
psql: could not connect to server: Connection refused
    Is the server running on host "localhost" (::1) and accepting
    TCP/IP connections on port 5432?
could not connect to server: Connection refused
    Is the server running on host "localhost" (127.0.0.1) and accepting
    TCP/IP connections on port 5432?