Update README.

1 files changed, 19 insertions, 1 deletions

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@@ -10,4 +10,22 @@ The final product is hosting on my [Tencent Cloud](https://cloud.tencent.com/) C
 
 Feel free to comment by opening an issue.
 
-`tools/open-code` file is a simple *bash* script that fixes the problem that *OminiSharp* in C# extension on vscode can't work using *dotnet* in Arch official package repository on Arch Linux. See [this page](https://bugs.archlinux.org/task/60903).
+`tools/open-code` file is a simple _bash_ script that fixes the problem that _OminiSharp_ in C# extension on vscode can't work using _dotnet_ in Arch official package repository on Arch Linux. See [this page](https://bugs.archlinux.org/task/60903).
+
+## about database configuration
+
+You can configure two database, one for development, other for production, at the same time in the configuration file (better in user secret file):
+
+```json
+{
+  "DatabaseConfig": {
+    "UseDevelopment": true,
+    "ConnectionString": "The secret production database string. (MySql)",
+    "DevelopmentConnectionString": "The private development database string. (Sqlite)"
+  }
+}
+```
+
+Set `UseDevelopment` to `true` to use `DevelopmentConnectionString` as sqlite connection string. Set `UseDevelopment` to `false` to use `ConnectionString` as mysql connection string. Usually you set it to `true` in development mode and `false` in production mode. But you may have to use production database to do migration in development so you may also set it to `false` in development to do that. The migrations for two database are different because they use different providers and remember to use it to switch to right database when do migration.
+
+If you have better solution to deal with database, please don't hesitate to tell me. 😛