として出力結果をパイプでファイルに書き出します。 ファイルの中身を見てみると、以下のような形でその時のデータベースの状態がSQLを使って再現できるような情報として記録されています。 -- -- PostgreSQL database dump -- <略> -- -- Name: foo; Type: TABLE; Schema: public; Owner: postgres; Tablespace: -- CREATE TABLE foo ( a integer NOT NULL, b text ); <略> -- -- Data for Name: foo; Type: TABLE DATA; Schema: public; Owner: postgres -- COPY foo (a, b) FROM stdin; 1 inserted 2 inserted 3 inserted
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