备份
一般来说备份分为两种，备份表，或者备份库
备份表，采用sql模式。
pg_dump -U postgres -d postgres -t
table_name -f /data/backup/
table_name.sql
如果单表太大，我们采用-Fc的模式，
pg_dump -U postgres -d postgres -Fc -t
table_name -f /data/backup/
table_name.dmp
看一下导出的sql文件
**********************************************************************************************
--
-- PostgreSQL database dump
--
-- Dumped from database version 10.4
-- Dumped by pg_dump version 10.4
SET statement_timeout = 0;
SET lock_timeout = 0;
SET idle_in_transaction_session_timeout = 0;
SET client_encoding = 'UTF8';
SET standard_conforming_strings = off;
SELECT pg_catalog.set_config('search_path', '', false);
SET check_function_bodies = false;
SET client_min_messages = warning;
SET escape_string_warning = off;
SET row_security = off;
SET default_tablespace = '';
SET default_with_oids = false;
--
-- Name: test01; Type: TABLE; Schema: public; Owner: mytest
--
CREATE TABLE public.test01 (
id integer DEFAULT nextval('public.seq_test01_id'::regclass) NOT NULL,
col1 character varying(10)
);
ALTER TABLE public.test01 OWNER TO mytest;
--
-- Data for Name: test01; Type: TABLE DATA; Schema: public; Owner: mytest
--
COPY public.test01 (id, col1) FROM stdin;
1 aaa
2 bbb
\.
--
-- PostgreSQL database dump complete
--
**********************************************************************************************
## 说明：
## 在建表语句中存在序列，但是导出文件中没有创建序列的语句，说明需要自己创建相关序列
# 备份数据库
pg_dump -U postgres -d mytest -f /data/mytest.sql
pg_dump -U postgres -d mytest -f /data/mytest.dmp -Fc
# 看一下备份数据库的sql文件（通过-Fc压缩过的导出dmp文件无法打开）。
**********************************************************************************************
--
-- PostgreSQL database dump
--
-- Dumped from database version 10.4
-- Dumped by pg_dump version 10.4
SET statement_timeout = 0;
SET lock_timeout = 0;
SET idle_in_transaction_session_timeout = 0;
SET client_encoding = 'UTF8';
SET standard_conforming_strings = off;
SELECT pg_catalog.set_config('search_path', '', false);
SET check_function_bodies = false;
SET client_min_messages = warning;
SET escape_string_warning = off;
SET row_security = off;
--
-- Name: plpgsql; Type: EXTENSION; Schema: -; Owner:
--
CREATE EXTENSION IF NOT EXISTS plpgsql WITH SCHEMA pg_catalog;
--
-- Name: EXTENSION plpgsql; Type: COMMENT; Schema: -; Owner:
--
COMMENT ON EXTENSION plpgsql IS 'PL/pgSQL procedural language';
--
-- Name: seq_mytest_id; Type: SEQUENCE; Schema: public; Owner: mytest
--
CREATE SEQUENCE public.seq_mytest_id
START WITH 1
INCREMENT BY 1
NO MINVALUE
NO MAXVALUE
CACHE 1;
ALTER TABLE public.seq_mytest_id OWNER TO mytest;
--
-- Name: seq_test01_id; Type: SEQUENCE; Schema: public; Owner: mytest
--
CREATE SEQUENCE public.seq_test01_id
START WITH 1
INCREMENT BY 1
NO MINVALUE
NO MAXVALUE
CACHE 1;
ALTER TABLE public.seq_test01_id OWNER TO mytest;
SET default_tablespace = '';
SET default_with_oids = false;
--
-- Name: test01; Type: TABLE; Schema: public; Owner: mytest
--
CREATE TABLE public.test01 (
id integer DEFAULT nextval('public.seq_test01_id'::regclass) NOT NULL,
col1 character varying(10)
);
ALTER TABLE public.test01 OWNER TO mytest;
--
-- Data for Name: test01; Type: TABLE DATA; Schema: public; Owner: mytest
--
COPY public.test01 (id, col1) FROM stdin;
1 aaa
2 bbb
\.
--
-- Name: seq_mytest_id; Type: SEQUENCE SET; Schema: public; Owner: mytest
--
SELECT pg_catalog.setval('public.seq_mytest_id', 1, false);
--
-- Name: seq_test01_id; Type: SEQUENCE SET; Schema: public; Owner: mytest
--
SELECT pg_catalog.setval('public.seq_test01_id', 2, true);
--
-- PostgreSQL database dump complete
--
**********************************************************************************************
# 注意：
# 备份数据库中没有说明数据库名称，所以在恢复的时候需要首先创建数据库，并在恢复命令中指明恢复到哪个数据库
恢复
# 如果备份的时候没有加-Fc参数，备份成sql文件的时候，恢复就要使用psql去执行。