PostgresSQL のerror Postgres PG::ConnectionBad: 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"? - Qiita
環境macOS High Sierrapsql (9.6.4)homebrew でpostgresをinstallした一応Railsでつかっています。結論$ brew services …
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