Merge pull request #16 from Glacier-Ice/add-db-doc

add database instructions

db/README.md

@@ -1,3 +1,21 @@
+We recommend to use postgres docker to run the database server:
+```
+docker pull postgres:10
+docker run -it --rm -v $PWD:/data -e POSTGRES_PASSWORD=abc -p 5432:5432 postgres:10
+```
+Then in another shell terminal, use `psql -h 127.0.0.1 -p 5432 -U postgres` to
+connect to the server. Then
+```
+create database data;
+\c data;
+\i area_city.sql;
+\i area_province.sql;
+\i area_relation.sql;
+\i data/area_city_data.sql;
+\i data/area_province_data.sql;
+```
+Thus the database schema is successfully intialized.
+
 epidemic是go写的存储疫情数据代码，后面考虑用python改一下。现使用了两张表，详细如下：
 
 省级表：area_province
@@ -27,4 +45,3 @@ epidemic是go写的存储疫情数据代码，后面考虑用python改一下。
 | cured_count     | bigint  | 治愈数 |
 | dead_count      | bigint  | 死亡数 |
 | suspected_count | bigint  | 疑似数 |
-